20 mL Vial & 30 mL Centrifuge Tube Screw Caps — HDPE, Lavender, 1000/Bag (300-3532-L20)
These lavender High-Density Polyethylene screw caps are engineered to fit Caplugs® Evergreen 20 mL screw-neck vials and 30 mL centrifuge tubes, supplied non-sterile in convenient 1000/Bag packs for high-throughput laboratory and biorepository workflows. The lavender color mirrors the CLSI H3 lavender-top EDTA anticoagulant convention, making these caps ideal for visually routing large-volume EDTA-preserved specimens — such as those used in molecular testing, HbA1c correlation studies, and CBC reference programs — without process retraining. Part number 300-3532-L20 is one of 15 colors in the 300-3532 range, all sharing identical HDPE material and thread geometry.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3532-L20 |
| Cap Type | Screw cap — threaded engagement |
| Material | High-Density Polyethylene (HDPE) |
| Color | Lavender |
| Tube Compatibility | Caplugs® Evergreen 20 mL screw-neck vials; 30 mL centrifuge tubes |
| Thread Note | Larger thread than 300-3010/300-3022 (15 mL cap family) — not interchangeable |
| Sterility | Non-Sterile |
| Cryogenic Storage | Compatible to -80°C |
| Autoclave Compatibility | 121°C / 15 psi |
| IATA P650 Compliance | Leak-free primary container seal |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Pack Size | 1000/Bag |
| Country of Origin | USA (California) |
Applications
- Capping Caplugs® Evergreen 20 mL screw-neck vials for specimen storage and transport
- Sealing 30 mL centrifuge tubes for serum or cell separation spins, with threaded engagement retaining the cap through centrifuge forces
- IATA P650 compliant closure for biological specimen transport in 20 mL and 30 mL tube formats
- Large-volume EDTA specimen routing (molecular diagnostics, HbA1c correlation, CBC reference studies) using lavender color coding per CLSI H3 convention
- Biorepository archiving of large-format tubes at -20°C and -80°C ultra-low temperature
- Cell culture incubation in 30 mL tubes — HDPE is compatible with standard culture media formulations
- Environmental and field sampling where chemical inertness to water and soil matrices is required
- Replacement cap programs for existing 20 mL vial and 30 mL tube inventory — thread specification matches Caplugs® Evergreen 20/30 mL tube family
Compatibility
These caps are designed specifically for Caplugs® Evergreen 20 mL screw-neck vials and 30 mL centrifuge tubes. The 300-3532 thread specification is larger than that of the 300-3010 and 300-3022 families used with 15 mL tubes, and the two thread sizes are not interchangeable. Laboratories sourcing replacement caps for existing 20 mL or 30 mL Caplugs® Evergreen tube inventory should confirm tube format before placing a bulk order — validate cap-to-tube thread fit with a sample quantity first.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers, saline, water | Excellent |
| Dilute acids and bases | Good |
| Ethanol and common alcohols | Good — short-term contact |
| Culture media formulations | Good |
| Chlorinated solvents (chloroform, DCM) | Not recommended |
| Aromatic solvents (toluene, xylene) | Not recommended |
| Cryogenic storage (to -80°C) | Compatible |
| Autoclave (121°C / 15 psi) | Compatible |
Quality & Procurement
Made in USA (California), these Caplugs® Evergreen caps are produced from BPA-free, phthalate-free HDPE resin and meet IATA P650 requirements for leak-free primary container seals in biological specimen transport. The lavender color is consistent across the full 300-3532 fifteen-color range, with all variants sharing identical material specification and thread geometry — color is the only variable, simplifying inventory management across multi-color routing programs. LabSupplies.com is an authorized Caplugs® Evergreen dealer and ships from USA inventory, with tiered pricing available for high-volume institutional and biorepository accounts.
Frequently Asked Questions
Will these caps fit my existing 15 mL centrifuge tubes?
No. The 300-3532 series uses a larger thread specification than the 300-3010 and 300-3022 cap families designed for 15 mL tubes. These caps are sized for Caplugs® Evergreen 20 mL screw-neck vials and 30 mL centrifuge tubes only. Confirm your tube format and validate fit with a sample before bulk ordering.
Are these caps suitable for ultra-low temperature biorepository storage?
Yes. HDPE maintains dimensional stability and seal integrity at -20°C and -80°C, making these caps appropriate for large-format tube archiving in biorepository programs.
Why are the caps lavender — is there a functional reason beyond color coding?
The lavender color mirrors the CLSI H3 lavender-top EDTA anticoagulant convention. In clinical and research labs handling large-volume EDTA-preserved specimens (molecular assays, HbA1c correlation studies, CBC reference work), lavender cap color provides immediate visual routing without additional labeling. All 15 colors in the 300-3532 range share identical HDPE material and thread geometry — color is the sole differentiator.
Can these caps be autoclaved for pre-sterilized supply chains?
Yes. HDPE is autoclave-compatible at 121°C / 15 psi, so caps can be sterilized prior to use in workflows that require a pre-sterilized closure. Note that caps are supplied non-sterile as shipped.