Sterile LDPE Two-Position Snap Caps for 17 mm PS Test Tubes — 1000/Bag (222-3817-02S)
These sterile Low-Density Polyethylene snap caps are precision-fitted for 17 mm OD polystyrene test tubes — including the standard 16.0 mL round-bottom PS tube format — and ship in bulk 1000/Bag packaging for high-volume laboratory workflows. The two-position snap mechanism delivers a vented position for gas exchange and a fully closed position for sealed storage or transport, all in a single cap. Made in USA from BPA-free, phthalate-free, FDA-compliant LDPE resin, part number 222-3817-02S completes the four-SKU Caplugs® Evergreen snap cap set alongside 12 mm and 17 mm PP and PS variants.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 222-3817-02S |
| Cap Material | Low-Density Polyethylene (LDPE) |
| Color | Natural |
| Compatible Tube Diameter | 17 mm OD |
| Compatible Tube Material | Polystyrene (PS) |
| Cap Positions | Position 1: Vented (partial open); Position 2: Fully Closed |
| Sterility | Sterile |
| Pack Size | 1000/Bag |
| BPA / Phthalate / Latex | BPA-Free, Phthalate-Free, Latex-Free |
| Country of Origin | USA |
Applications
- Capping 17 mm OD PS round-bottom tubes (including 16.0 mL format) for vented incubation or sealed storage
- Cell culture in PS tubes where CO₂ exchange is required in the vented position and a sealed closure is needed for transport
- Centrifugation workflows where the vented position allows pressure equalization during spinning
- Serology and flow cytometry — snap re-sealing between agglutination, staining, and reading steps on 16 mL PS tubes
- Replacement of damaged or missing OEM caps on 17 mm PS tubes; sterile and dimensionally matched to PS tube wall tolerances
- High-consumption labs requiring bulk sterile cap inventory for routine 16 mL tube processing
Compatibility
These caps are dimensionally optimized for the wall tolerances of 17 mm OD polystyrene test tubes, including the standard 16.0 mL round-bottom PS tube format widely used in clinical chemistry, serology, and research laboratories. The flexible LDPE snap mechanism achieves a secure fit specifically on PS tube outer diameters; for 17 mm polypropylene tubes, Caplugs® Evergreen offers the companion SKU 222-3817-02P. The complete four-SKU snap cap set — 12 mm PP (222-3812-02P), 12 mm PS (222-3812-02S), 17 mm PP (222-3817-02P), and 17 mm PS (222-3817-02S) — covers the primary round-bottom tube diameter and material combinations used across most clinical and research tube inventories.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / saline | Excellent |
| Cell culture media | Excellent — low extractables for biological contact |
| Formalin (10%) | Excellent — compatible for fixation steps |
| Ethanol (<70%) | Good — short-term contact |
| Acetonitrile | Limited — avoid prolonged contact |
| Dichloromethane | Not Compatible — causes swelling; do not use |
| Autoclaving | Not Recommended — sterile single-use; ~60°C max |
| Cryogenic temperatures | Not Rated — not designed for liquid nitrogen contact |
Quality & Procurement
Made in USA, these Caplugs® Evergreen snap caps are produced from FDA-compliant, BPA-free, phthalate-free, and latex-free LDPE resin, and are supplied sterile for immediate use in clinical and research environments. LabSupplies.com is an authorized dealer and ships from USA inventory, typically same business day for stocking items. The 1000/Bag format is well suited for institutional procurement, high-volume labs, and grant-funded facilities seeking competitive per-unit economics on routine consumables.
Frequently Asked Questions
Are these snap caps sterile right out of the bag?
Yes — the 222-3817-02S is supplied sterile and is intended as a single-use closure. They should not be autoclaved; the LDPE material is rated to approximately 60°C and is not designed for steam sterilization cycles.
What is the difference between the two snap positions?
Position 1 is a vented (partial-open) configuration that allows gas exchange — useful during cell culture incubation or centrifugation for pressure equalization. Position 2 is fully closed and provides a sealed closure for storage, transport, or steps that require containment between reads.
Will these caps fit polypropylene tubes of the same diameter?
These caps are dimensionally optimized for 17 mm OD polystyrene tube wall tolerances. For 17 mm PP tubes, Caplugs® Evergreen offers the companion SKU 222-3817-02P, which is engineered to the slightly different dimensional tolerances of polypropylene tube formats.
Can these caps be reused after opening?
While the snap mechanism allows the cap to be repositioned between vented and closed states during a single workflow, these are manufactured and supplied as single-use sterile items. Reuse after removal from the tube is not recommended where sterility must be maintained.