{"product_id":"caplugs-300-3812-02s-ldpe-two-position-snap-cap-12mm-ps-test-tube","title":"Test Tubes, LDPE, Natural — 300-3812-02S | 1000\/Bag | Caplugs® Evergreen","description":"\u003ch2\u003eTwo-Position Snap Caps, For 12 mm PS Test Tubes, LDPE, Natural — 300-3812-02S | 1000\/Bag\u003c\/h2\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e\u003cth colspan=\"2\"\u003eQuick Reference — 300-3812-02S\u003c\/th\u003e\u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003eTube Format\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003e12 mm PS test tubes\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003eCap Type\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003eTwo-position snap cap (partial-open + fully closed)\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003eMaterial\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003eLow-Density Polyethylene (LDPE)\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003eColor\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003eNatural\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003ePosition 1\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003ePartial-open — allows gas exchange during incubation\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003ePosition 2\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003eFully closed — sealed for storage and transport\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003evs Stoppers\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003eSnap cap stays attached between positions; stopper must be removed\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003eSterility\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003eNon-Sterile\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003ePack Size\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003e1000 \/ Bag\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003ePrice\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003e$56.57 \/ Bag ($0.0566 \/ cap)\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eTechnical Narrative\u003c\/h2\u003e \u003cp\u003eThe Caplugs® Evergreen is an LDPE two-position snap cap for 12 mm PS test tubes — a cap that provides two distinct functional positions without being removed from the tube. The partial-open (first snap) position holds the cap ajar, allowing CO₂ and O₂ gas exchange during microbiology culture tube incubation — maintaining the aerobic or microaerophilic atmosphere required by the growing culture without contamination risk from an uncapped tube. The fully-closed (second snap) position seals the tube completely for refrigerated storage, frozen archiving, and transport without contamination risk.\u003c\/p\u003e \u003cp\u003eThe two-position snap cap's key workflow advantage over a simple stopper cap is that it remains attached to the tube throughout both positions — eliminating the need to set down, find, or replace a loose cap when switching between incubation (partial-open) and storage (closed) modes. LDPE construction provides the flex required for the snap-position engagement mechanism across the repeated open\/close cycling of a microbiology culture workflow. The PS tube variant  is specifically dimensioned for 12 mm PS test tubes — the PP variant (300-3812-02P) fits 12 mm PP tubes.\u003c\/p\u003e \u003cp\u003eAt $56.57 per 1000\/Bag — $0.0566 per cap. For 12 mm PP tubes, see 300-3812-02P ($56.57\/1000).\u003c\/p\u003e \u003ch2\u003eTechnical Specifications — Caplugs® Evergreen \u003c\/h2\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e \u003cth\u003eSpecification\u003c\/th\u003e \u003cth\u003eValue\u003c\/th\u003e \u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd\u003ePart Number\u003c\/td\u003e \u003ctd\u003e\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eCaplugs Item #\u003c\/td\u003e \u003ctd\u003e300381202SE1\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eTube Format\u003c\/td\u003e \u003ctd\u003e12 mm PS test tubes\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eCap Style\u003c\/td\u003e \u003ctd\u003eTwo-position snap cap\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003ePosition 1\u003c\/td\u003e \u003ctd\u003ePartial-open — gas exchange \/ venting\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003ePosition 2\u003c\/td\u003e \u003ctd\u003eFully closed — sealed\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eMaterial\u003c\/td\u003e \u003ctd\u003eLow-Density Polyethylene (LDPE)\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eColor\u003c\/td\u003e \u003ctd\u003eNatural\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003evs PP variant\u003c\/td\u003e \u003ctd\u003eSame cap; 300-3812-02P fits 12 mm PP tubes\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eSterility\u003c\/td\u003e \u003ctd\u003eNon-Sterile\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003ePack Size\u003c\/td\u003e \u003ctd\u003e1000 \/ Bag\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eBPA\/Phthalate\u003c\/td\u003e \u003ctd\u003eBPA-free; no phthalate plasticizers\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eCountry of Origin\u003c\/td\u003e \u003ctd\u003eMade in U.S.A. (California)\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eTwo-Position Snap Cap Application Compatibility — 12 mm PS\u003c\/h2\u003e \u003cp\u003eThe LDPE snap cap fits 12 mm PS test tubes for workflows requiring both gas exchange and sealed closure:\u003c\/p\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e \u003cth\u003eApplication\u003c\/th\u003e \u003cth\u003eTube \/ Specimen\u003c\/th\u003e \u003cth\u003eNotes\u003c\/th\u003e \u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd\u003e12 mm test tube closure\u003c\/td\u003e \u003ctd\u003e12 mm OD culture and test tubes\u003c\/td\u003e \u003ctd\u003eTwo-position snap: partial open (gas exchange) or fully closed\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eMicrobiology culture tube capping\u003c\/td\u003e \u003ctd\u003eBroth culture tubes (TSB, BHI, LB)\u003c\/td\u003e \u003ctd\u003ePartial-open position allows CO2\/O2 exchange during incubation\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eSealed storage position\u003c\/td\u003e \u003ctd\u003eRefrigerated or frozen tube storage\u003c\/td\u003e \u003ctd\u003eClosed position provides sealed contamination-free storage\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eClinical chemistry tube closure\u003c\/td\u003e \u003ctd\u003eSample tubes staged before analysis\u003c\/td\u003e \u003ctd\u003eClosed position prevents evaporation during pre-analytical hold\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eCell culture tube capping\u003c\/td\u003e \u003ctd\u003eSuspension culture, virus propagation tubes\u003c\/td\u003e \u003ctd\u003ePartial-open for gas exchange; closed for transport\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eSequential open\/close cycling\u003c\/td\u003e \u003ctd\u003eTubes accessed multiple times per workflow\u003c\/td\u003e \u003ctd\u003eTwo-position snap allows repeated open\/close without degradation\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eEnvironmental sampling\u003c\/td\u003e \u003ctd\u003eField collection tube closure\u003c\/td\u003e \u003ctd\u003eClosed snap position for transport; open for field sampling\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eColor routing (natural cap)\u003c\/td\u003e \u003ctd\u003eUniversal tube cap for any labeling system\u003c\/td\u003e \u003ctd\u003eNatural LDPE cap for secondary label identification\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003cp\u003e\u003cem\u003eValidate snap-cap fit with your specific tube brand. For PP tubes, use 300-3812-02P.\u003c\/em\u003e\u003c\/p\u003e \u003ch2\u003eChemical Resistance — Low-Density Polyethylene (LDPE)\u003c\/h2\u003e \u003cp\u003eLDPE provides flexibility for snap-cap position engagement and inertness to culture media and specimen matrices.\u003c\/p\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e \u003cth\u003eReagent \/ Condition\u003c\/th\u003e \u003cth\u003eCompatibility\u003c\/th\u003e \u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd\u003eAqueous buffers \/ water\u003c\/td\u003e \u003ctd\u003e✓ Excellent\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eUrine \/ serum \/ plasma\u003c\/td\u003e \u003ctd\u003e✓ Excellent\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eDilute acids (\u0026lt;10%)\u003c\/td\u003e \u003ctd\u003e✓ Good\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eShort-chain alcohols (brief)\u003c\/td\u003e \u003ctd\u003e✓ Good\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eDMSO (≤10%)\u003c\/td\u003e \u003ctd\u003e✓ Good\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eAutoclave (121°C)\u003c\/td\u003e \u003ctd\u003e✗ Not compatible — LDPE softens\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eStorage at -20°C\u003c\/td\u003e \u003ctd\u003e✓ Suitable — LDPE retains flexibility\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003e300-3812 Two-Position Snap Cap Tube Variants\u003c\/h2\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e \u003cth\u003ePart Number\u003c\/th\u003e \u003cth\u003eTube Material\u003c\/th\u003e \u003cth\u003ePrice\/1000\u003c\/th\u003e \u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd\u003e\u003cstrong\u003e\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003e\u003cstrong\u003e12 mm PS\u003c\/strong\u003e\u003c\/td\u003e \u003ctd\u003e$56.57\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003e300-3812-02P\u003c\/td\u003e \u003ctd\u003e12 mm PP\u003c\/td\u003e \u003ctd\u003e$56.57\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eLaboratory Applications\u003c\/h2\u003e \u003cp\u003eThe serves microbiology labs running broth culture in 12 mm PS tubes where gas exchange during incubation and sealed storage between runs are sequential requirements; clinical microbiology programs using 12 mm culture tubes; cell culture programs using 12 mm tubes requiring vented incubation; and any 12 mm PS tube workflow requiring the two-position partial-open \/ fully-closed cap functionality.\u003c\/p\u003e \u003ch2\u003eU.S. Manufacturing, Quality \u0026amp; Institutional Procurement\u003c\/h2\u003e \u003cp\u003eEvery Caplugs® Evergreen lot is precision-molded at our California manufacturing facility. We supply reference laboratories, hospital systems, and federal procurement offices under institutional pricing programs with blanket-order support and same-day shipping. \u003ca href=\"#request-sample\"\u003eRequest a free sample below\u003c\/a\u003e to validate fit before committing to volume.\u003c\/p\u003e \u003ch2\u003eFrequently Asked Questions — Caplugs® Evergreen \u003c\/h2\u003e \u003ch3\u003eWhat are the two positions on the two-position snap cap?\u003c\/h3\u003e \u003cp\u003ePosition 1 (partial-open \/ first snap): the cap is held ajar by the first snap engagement — a small gap allows gas exchange for culture tube incubation while preventing uncontrolled contamination from open tubes. Position 2 (fully closed \/ second snap): the cap is fully seated for sealed tube storage and transport. The cap remains attached to the tube in both positions — no loose cap to set down or misplace between incubation and storage cycles.\u003c\/p\u003e \u003ch3\u003eWhat is the difference between the PS variant  and the PP variant (300-3812-02P)?\u003c\/h3\u003e \u003cp\u003eBoth are LDPE two-position snap caps for 12 mm test tubes — the only difference is the tube material they are dimensioned for. fits 12 mm PS (PS) test tubes. 300-3812-02P fits 12 mm PP (PP) test tubes. PP and PS test tubes can have slightly different wall thicknesses for the same OD, requiring different snap cap dimensions for positive retention. Always validate with a sample before bulk purchase.\u003c\/p\u003e \u003ch3\u003eCan the two-position snap cap be used as a full stopper replacement?\u003c\/h3\u003e \u003cp\u003eThe two-position snap cap functions as a tube closure in both positions, but the partial-open position is specifically designed for gas exchange — it is not a fully sealed closure. For applications requiring a complete hermetic seal in all conditions, use LDPE stopper caps (300-2912 series for 12 mm tubes) which provide full friction-fit closure when inserted. The two-position snap cap is the correct choice when alternating between vented incubation and sealed storage without cap removal is the workflow requirement.\u003c\/p\u003e \u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"Product\",\n  \"name\": \"Two-Position Snap Caps, For 12 mm PS Test Tubes, Non-Sterile, Low-Density Polyethylene (LDPE), Natural \\u2014 300-3812-02S | 1000\/Bag | Caplugs\\u00ae Evergreen\",\n  \"description\": \"Caplugs\\u00ae Evergreen 300-3812-02S. LDPE two-position snap caps for 12 mm PS test tubes, natural, 1000\/Bag. Vented + sealed positions. BPA-free. USA.\",\n  \"sku\": \"300381202SE1\",\n  \"mpn\": \"300-3812-02S\",\n  \"material\": \"Low-Density Polyethylene (LDPE)\",\n  \"color\": \"Natural\",\n  \"brand\": {\n    \"@type\": \"Brand\",\n    \"name\": \"Caplugs\\u00ae Evergreen\"\n  },\n  \"manufacturer\": {\n    \"@type\": \"Organization\",\n    \"name\": \"Caplugs\\u00ae Evergreen\",\n    \"address\": {\n      \"@type\": \"PostalAddress\",\n      \"addressCountry\": \"US\",\n      \"addressRegion\": \"CA\"\n    }\n  },\n  \"offers\": {\n    \"@type\": \"Offer\",\n    \"price\": \"56.57\",\n    \"priceCurrency\": \"USD\",\n    \"availability\": \"https:\/\/schema.org\/InStock\",\n    \"itemCondition\": \"https:\/\/schema.org\/NewCondition\",\n    \"seller\": {\n      \"@type\": \"Organization\",\n      \"name\": \"LabSupplies\"\n    }\n  },\n  \"additionalProperty\": [\n    {\n      \"@type\": \"PropertyValue\",\n      \"name\": \"Tube Compatibility\",\n      \"value\": \"12 mm PS test tubes\"\n    },\n    {\n      \"@type\": \"PropertyValue\",\n      \"name\": \"Pack Size\",\n      \"value\": \"1000 \/ Bag\"\n    },\n    {\n      \"@type\": \"PropertyValue\",\n      \"name\": \"Sterility\",\n      \"value\": \"Non-Sterile\"\n    },\n    {\n      \"@type\": \"PropertyValue\",\n      \"name\": \"Country of Origin\",\n      \"value\": \"United States\"\n    },\n    {\n      \"@type\": \"PropertyValue\",\n      \"name\": \"BPA Free\",\n      \"value\": \"Yes\"\n    }\n  ]\n}\n\u003c\/script\u003e \u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What are the two positions on the two-position snap cap?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Position 1 (partial-open \/ first snap): the cap is held ajar by the first snap engagement \\u2014 a small gap allows gas exchange for culture tube incubation while preventing uncontrolled contamination from open tubes. Position 2 (fully closed \/ second snap): the cap is fully seated for sealed tube storage and transport. The cap remains attached to the tube in both positions \\u2014 no loose cap to set down or misplace between incubation and storage cycles.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the difference between the PS variant (300-3812-02S) and the PP variant (300-3812-02P)?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Both are LDPE two-position snap caps for 12 mm test tubes \\u2014 the only difference is the tube material they are dimensioned for. 300-3812-02S fits 12 mm PS (PS) test tubes. 300-3812-02P fits 12 mm PP (PP) test tubes. PP and PS test tubes can have slightly different wall thicknesses for the same OD, requiring different snap cap dimensions for positive retention. Always validate with a sample before bulk purchase.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can the two-position snap cap be used as a full stopper replacement?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The two-position snap cap functions as a tube closure in both positions, but the partial-open position is specifically designed for gas exchange \\u2014 it is not a fully sealed closure. For applications requiring a complete hermetic seal in all conditions, use LDPE stopper caps (300-2912 series for 12 mm tubes) which provide full friction-fit closure when inserted. The two-position snap cap is the correct choice when alternating between vented incubation and sealed storage without cap removal is the workflow requirement.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"Caplugs® Evergreen","offers":[{"title":"Default Title","offer_id":48567931732200,"sku":"300-3812-02S","price":56.57,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0694\/5361\/1240\/files\/300-3812-02S_03_4b1abe02-6655-45f2-a00d-8d384032881b.jpg?v=1779074477","url":"https:\/\/labsupplies.com\/products\/caplugs-300-3812-02s-ldpe-two-position-snap-cap-12mm-ps-test-tube","provider":"LabSupplies.com","version":"1.0","type":"link"}