{"product_id":"222-3812-02s-snap-cap-only","title":"Test Tubes, LDPE, Natural — 222-3812-02S | 1000\/Bag | Caplugs® Evergreen","description":"\u003ch2\u003eQuick Reference\u003c\/h2\u003e \u003ctable\u003e \u003ctbody\u003e \u003ctr\u003e \u003cth\u003ePart Number\u003c\/th\u003e \u003ctd\u003e222-3812-02S\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eProduct\u003c\/th\u003e \u003ctd\u003eTwo-position snap caps for 12 mm PS test tubes\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCap Material\u003c\/th\u003e \u003ctd\u003eLow-Density Polyethylene (LDPE)\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eColor\u003c\/th\u003e \u003ctd\u003eNatural\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eTube Diameter\u003c\/th\u003e \u003ctd\u003e12 mm OD\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eTube Material\u003c\/th\u003e \u003ctd\u003ePS (optimized fit for PS tube wall dimensions)\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCap Function\u003c\/th\u003e \u003ctd\u003eTwo positions: vented (partial open) + fully closed\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003ePack Size\u003c\/th\u003e \u003ctd\u003e1000\/Bag\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eSterility\u003c\/th\u003e \u003ctd\u003eSterile\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eOrigin\u003c\/th\u003e \u003ctd\u003eMade in USA\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003ePrice\u003c\/th\u003e \u003ctd\u003e$62.77\/Bag ($0.0628\/cap)\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eTechnical Narrative\u003c\/h2\u003e \u003cp\u003eThe Caplugs® Evergreen \u003cstrong\u003e222-3812-02S\u003c\/strong\u003e provides \u003cstrong\u003eSterile LDPE Two-Position Snap Caps\u003c\/strong\u003e for \u003cstrong\u003e12 mm PS test tubes\u003c\/strong\u003e, 1000\/Bag. These are bulk sterile cap supply for round-bottom and conical test tubes with 12 mm outer diameter in PS — compatible with the Caplugs Evergreen 222-series sterile test tubes that use the two-position snap cap closure. The two-position mechanism provides: \u003cstrong\u003ePosition 1 (vented)\u003c\/strong\u003e — partial open for gas exchange during centrifugation, incubation, or culture; \u003cstrong\u003ePosition 2 (closed)\u003c\/strong\u003e — fully sealed for storage, transport, and aerosol containment. LDPE's flexibility enables the snap mechanism to function reliably with PS's dimensional tolerances.\u003c\/p\u003e \u003cp\u003e\u003cstrong\u003eLow-Density Polyethylene (LDPE)\u003c\/strong\u003e: flexible snap mechanism, broad chemical resistance, low extractables for biological contact. Sterile 1000\/Bag — high-volume cap supply for bulk tube assembly or replacement cap inventory. BPA-free, phthalate-free, \u003c\/p\u003e \u003cp\u003eProcurement economics: \u003cstrong\u003e$62.77\/Bag (1000 caps)\u003c\/strong\u003e, \u003cstrong\u003e$0.0628\/cap\u003c\/strong\u003e. Size\/material set: \u003cstrong\u003e222-3812-02P\u003c\/strong\u003e (12 mm PP tube snap caps 1000\/Bag); \u003cstrong\u003e222-3817-02P\u003c\/strong\u003e (17 mm PP tube snap caps 1000\/Bag). LabSupplies.com ships from USA inventory, typically same business day.\u003c\/p\u003e \u003ch2\u003eTechnical Specifications\u003c\/h2\u003e \u003ctable\u003e \u003ctbody\u003e \u003ctr\u003e \u003cth\u003ePart Number\u003c\/th\u003e \u003ctd\u003e\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCaplugs Item #\u003c\/th\u003e \u003ctd\u003e\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eProduct\u003c\/th\u003e \u003ctd\u003eTwo-position snap caps for 12 mm PS test tubes\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCap Material\u003c\/th\u003e \u003ctd\u003eLow-Density Polyethylene (LDPE)\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eColor\u003c\/th\u003e \u003ctd\u003eNatural\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eTube Diameter\u003c\/th\u003e \u003ctd\u003e12 mm OD\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eTube Material\u003c\/th\u003e \u003ctd\u003ePS\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCap Positions\u003c\/th\u003e \u003ctd\u003ePosition 1: vented (partial open); Position 2: fully closed\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eSterility\u003c\/th\u003e \u003ctd\u003eSterile\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003ePack Size\u003c\/th\u003e \u003ctd\u003e1000\/Bag\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eBPA \/ Phthalate\u003c\/th\u003e \u003ctd\u003eBPA-Free, Phthalate-Free, Latex-Free\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCountry of Origin\u003c\/th\u003e \u003ctd\u003eUSA \u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003ePrice\u003c\/th\u003e \u003ctd\u003e$62.77\/Bag ($0.0628\/cap)\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eTwo-Position Snap Cap (12 mm PS Tube) Applications\u003c\/h2\u003e \u003cp\u003eThe snap cap is compatible with 12 mm OD PS round-bottom test tubes requiring a two-position vented\/closed closure.\u003c\/p\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e \u003cth\u003eApplication\u003c\/th\u003e \u003cth\u003eSetting \/ Configuration\u003c\/th\u003e \u003cth\u003eNotes\u003c\/th\u003e \u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003cth\u003eTube capping at bench\u003c\/th\u003e \u003ctd\u003e12 mm PS round-bottom tube\u003c\/td\u003e \u003ctd\u003eSnap on for instant closure; two-position for vented use\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCell culture in tube\u003c\/th\u003e \u003ctd\u003eIncubator, vented position on 12mm PS\u003c\/td\u003e \u003ctd\u003eVented: CO2 exchange during incubation; closed: transport\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eCentrifugation with venting\u003c\/th\u003e \u003ctd\u003eClinical centrifuge, vented snap cap\u003c\/td\u003e \u003ctd\u003eVented position equalizes pressure during centrifuge spin\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eBulk cap inventory\u003c\/th\u003e \u003ctd\u003eHigh-volume tube processing lab\u003c\/td\u003e \u003ctd\u003e1000\/Bag for labs consuming caps at high daily rates\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eReplacement cap supply\u003c\/th\u003e \u003ctd\u003eReplace damaged caps on 12mm PS tubes\u003c\/td\u003e \u003ctd\u003eSterile; exact material match for tube tolerance\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eSerology tube panel\u003c\/th\u003e \u003ctd\u003e12mm PS tube agglutination panel\u003c\/td\u003e \u003ctd\u003eSnap cap re-seals after reading for incubation continuation\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003cth\u003eFlow cytometry prep\u003c\/th\u003e \u003ctd\u003e12mm PS tube, vented during staining\u003c\/td\u003e \u003ctd\u003eVented position during incubation steps; closed for reading\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eChemical Resistance — Low-Density Polyethylene (LDPE)\u003c\/h2\u003e \u003cp\u003eCompatibility reference for LDPE at typical laboratory conditions.\u003c\/p\u003e \u003ctable\u003e \u003cthead\u003e\u003ctr\u003e \u003cth\u003eReagent \/ Condition\u003c\/th\u003e \u003cth\u003eCompatibility\u003c\/th\u003e \u003cth\u003eNotes\u003c\/th\u003e \u003c\/tr\u003e\u003c\/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd\u003eAqueous buffers \/ saline\u003c\/td\u003e \u003ctd\u003eExcellent\u003c\/td\u003e \u003ctd\u003eLDPE inert across standard biological buffer pH range.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eCell culture media\u003c\/td\u003e \u003ctd\u003eExcellent\u003c\/td\u003e \u003ctd\u003eStandard biological contact matrix; low extractables.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eEthanol (\u0026lt;70%)\u003c\/td\u003e \u003ctd\u003eGood\u003c\/td\u003e \u003ctd\u003eShort-term compatible for standard staining solutions.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eMethanol (\u0026lt;50%)\u003c\/td\u003e \u003ctd\u003eGood\u003c\/td\u003e \u003ctd\u003eShort-term compatible.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eAcetonitrile\u003c\/td\u003e \u003ctd\u003eLimited\u003c\/td\u003e \u003ctd\u003eAvoid prolonged LDPE contact; LDPE for aqueous protocols.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eFormalin (10%)\u003c\/td\u003e \u003ctd\u003eExcellent\u003c\/td\u003e \u003ctd\u003eCompatible with standard fixative for post-culture fixation.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eDichloromethane \/ chloroform\u003c\/td\u003e \u003ctd\u003eNot Compatible\u003c\/td\u003e \u003ctd\u003eCauses swelling; do not use.\u003c\/td\u003e \u003c\/tr\u003e \u003ctr\u003e \u003ctd\u003eTemperature\u003c\/td\u003e \u003ctd\u003e~60°C max\u003c\/td\u003e \u003ctd\u003eLDPE: do not autoclave; sterile-packed single-use.\u003c\/td\u003e \u003c\/tr\u003e \u003c\/tbody\u003e \u003c\/table\u003e \u003ch2\u003eClinical \u0026amp; Research Laboratory Applications\u003c\/h2\u003e \u003cp\u003eCaplugs® Evergreen sterile LDPE two-position snap caps for 12 mm PS test tubes serve clinical serology, flow cytometry, cell biology, and microbiology laboratories requiring bulk sterile cap supply for their round-bottom PS tube inventory. The two-position snap cap is the standard closure for flow cytometry and serology tubes — used across the Caplugs Evergreen 222-series sterile round-bottom tubes and compatible with other manufacturers' 12 mm PS tubes. Labs standardize on separate 1000\/Bag cap supply when: (1) they purchase tubes and caps independently for inventory flexibility; (2) they need replacement caps for tubes whose caps were damaged; (3) high daily cap consumption requires bulk economics not available in 25\/Bag assembled formats. The PP vs PS material designation reflects the dimensional fit optimization — PP and PS 12 mm tubes have slightly different wall profiles, and the correctly specified cap provides the most reliable snap engagement and release for each tube material.\u003c\/p\u003e \u003ch2\u003eU.S. Manufacturing, Quality \u0026amp; Institutional Procurement\u003c\/h2\u003e \u003cp\u003eCaplugs® Evergreen products are manufactured in the United States under ISO 9001 quality management from FDA-compliant, food-contact-grade resins. BPA-free, phthalate-free, and latex-free, with material-disclosure documentation supporting CAP, CLIA, and ISO 15189 laboratory accreditation audits.\u003c\/p\u003e \u003cp\u003eLabSupplies.com is an authorized dealer for the full Caplugs Evergreen catalog and ships directly from USA inventory — typically same business day for stocking SKUs. We offer below retail pricing on volume orders, tiered institutional and academic pricing, and direct support for grant-funded laboratories and government procurement channels. Lab managers and procurement officers can \u003ca href=\"#request-sample\"\u003erequest a written quote or speak with a product specialist\u003c\/a\u003e directly from our sales engineering team.\u003c\/p\u003e \u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e \u003ch3\u003eAre the snap caps sterile?\u003c\/h3\u003e \u003cp\u003eYes. Sterile — packed 1000\/Bag.\u003c\/p\u003e \u003ch3\u003eWhy is there a separate cap for PP tubes  vs PS tubes?\u003c\/h3\u003e \u003cp\u003ePP and PS 12 mm tubes have slightly different wall thicknesses and outer diameter tolerances due to the different physical properties of the two materials. The snap cap's engagement mechanism is dimensionally optimized for each tube material — the PP-specified cap provides reliable snap engagement on PP tubes, and the PS-specified cap on PS tubes. Using a mismatched cap may result in loose fit, over-tightness, or unreliable position engagement.\u003c\/p\u003e \u003ch3\u003eWhat is the two-position snap cap mechanism?\u003c\/h3\u003e \u003cp\u003ePosition 1 (vented\/partially open): the cap is clicked to the first detent, leaving a small gap that allows gas exchange — used during CO2 incubation, aerobic culture, and centrifugation where pressure equalization is needed. Position 2 (fully closed): the cap clicks to a fully sealed position for sample storage, transport, and aerosol containment. LDPE's flexibility allows reliable engagement at both positions throughout the tube's use cycle.\u003c\/p\u003e \u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\/\", \"@type\": \"Product\", \"name\": \"Caplugs® Evergreen 222-3812-02S | Two-Position Snap Caps for 12 mm PS Test Tubes, Sterile — LDPE, Natural, 1000\/Bag\", \"sku\": \"222381202SE1\", \"mpn\": \"222-3812-02S\", \"brand\": {\"@type\": \"Brand\", \"name\": \"Caplugs® Evergreen\"}, \"manufacturer\": {\"@type\": \"Organization\", \"name\": \"Caplugs® Evergreen\", \"address\": \"USA\"}, \"material\": \"Low-Density Polyethylene (LDPE)\", \"color\": \"Natural\", \"image\": \"https:\/\/prod-cp-cdn-images.azureedge.net\/catalog\/92300\/9093F9E9-0629-4E5F-B21B-39C8A1BB4B87\/300-3812-02S_03.jpg\", \"description\": \"Caplugs® Evergreen 222-3812-02S: Two-Position Snap Caps for 12 mm PS Test Tubes, Sterile, LDPE, Natural, 1000\/Bag. MADE IN USA, authorized dealer.\", \"additionalProperty\": [{\"@type\": \"PropertyValue\", \"name\": \"Product\", \"value\": \"Snap caps 12mm PS\"}, {\"@type\": \"PropertyValue\", \"name\": \"Material\", \"value\": \"Low-Density Polyethylene (LDPE)\"}, {\"@type\": \"PropertyValue\", \"name\": \"Tube Diameter\", \"value\": \"12 mm\"}, {\"@type\": \"PropertyValue\", \"name\": \"Pack\", \"value\": \"1000\/Bag\"}, {\"@type\": \"PropertyValue\", \"name\": \"Sterility\", \"value\": \"Sterile\"}, {\"@type\": \"PropertyValue\", \"name\": \"Origin\", \"value\": \"USA\"}], \"offers\": {\"@type\": \"Offer\", \"priceCurrency\": \"USD\", \"price\": \"62.77\", \"availability\": \"https:\/\/schema.org\/InStock\", \"url\": \"https:\/\/labsupplies.com\/products\/222-3812-02s-snap-cap-only\"}}\u003c\/script\u003e \u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\/\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"Are the 222-3812-02S snap caps sterile?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Yes. Sterile — packed 1000\/Bag.\"}}, {\"@type\": \"Question\", \"name\": \"Why is there a separate cap for PP tubes (222-3812-02S) vs PS tubes?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"PP and PS 12 mm tubes have slightly different wall thicknesses and outer diameter tolerances due to the different physical properties of the two materials. The snap cap's engagement mechanism is dimensionally optimized for each tube material — the PP-specified cap provides reliable snap engagement on PP tubes, and the PS-specified cap on PS tubes. Using a mismatched cap may result in loose fit, over-tightness, or unreliable position engagement.\"}}, {\"@type\": \"Question\", \"name\": \"What is the two-position snap cap mechanism?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Position 1 (vented\/partially open): the cap is clicked to the first detent, leaving a small gap that allows gas exchange — used during CO2 incubation, aerobic culture, and centrifugation where pressure equalization is needed. Position 2 (fully closed): the cap clicks to a fully sealed position for sample storage, transport, and aerosol containment. LDPE's flexibility allows reliable engagement at both positions throughout the tube's use cycle.\"}}]}\u003c\/script\u003e","brand":"Caplugs® Evergreen","offers":[{"title":"Default Title","offer_id":48567661723880,"sku":"222381202SE1","price":62.77,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0694\/5361\/1240\/files\/300-3812-02S_03_9d87025f-2d1e-4b6c-b942-e89760ab6e34.jpg?v=1779053278","url":"https:\/\/labsupplies.com\/products\/222-3812-02s-snap-cap-only","provider":"LabSupplies.com","version":"1.0","type":"link"}