20 mL Vial & 30 mL Centrifuge Tube Screw Caps — HDPE, White, 1000/Bag (300-3532-W20)
These white high-density polyethylene screw caps from Caplugs® Evergreen are designed to fit 20 mL screw-neck vials and 30 mL centrifuge tubes, delivering leak-free closure compliant with IATA P650 transport regulations. Supplied non-sterile in 1000/Bag bulk packaging, part number 300-3532-W20 supports biorepository archiving at –80°C, autoclave sterilization at 121°C, and high-throughput clinical specimen routing where a clean white surface provides maximum contrast for adhesive and LIS-printed barcode labels.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3532-W20 |
| Cap Type | Screw cap — threaded engagement |
| Material | High-Density Polyethylene (HDPE) |
| Color | White |
| Tube Compatibility | Caplugs® Evergreen 20 mL screw-neck vials; 30 mL centrifuge tubes |
| Thread Note | Larger thread than 300-3010/300-3022 family — not interchangeable |
| IATA P650 Compliance | Yes — leak-free primary container seal |
| Cryogenic Storage | Compatible to –80°C |
| Autoclave Compatibility | Compatible (121°C / 15 psi) |
| Sterility | Non-Sterile |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Pack Size | 1000/Bag |
| Country of Origin | USA |
Applications
- Capping 20 mL screw-neck vials for clinical chemistry, reference laboratory, and biorepository programs
- Leak-free closure of 30 mL centrifuge tubes for IATA P650–compliant specimen transport
- Biorepository archiving at –80°C, where HDPE cryo stability and the white cap surface maximize barcode label readability for LIS-integrated workflows
- Color-coded specimen batch routing across clinical departments — white offers the highest-contrast background for adhesive and thermal-printed labels
- Replacement cap supply for existing Caplugs® Evergreen 20 mL vial and 30 mL centrifuge tube inventory
- Capped centrifugation of 30 mL tubes — threaded engagement retains the cap through centrifuge forces
Compatibility
These caps are engineered specifically for Caplugs® Evergreen 20 mL screw-neck vials and the 30 mL centrifuge tube family. The 300-3532 thread specification is larger than that of the 300-3010 and 300-3022 cap families used on 15 mL tubes, so the two product families are not interchangeable. If you are transitioning from another cap supplier or evaluating a color-coded routing system, validate fit against your current tube stock with a sample quantity before placing a full bulk order. All caps within the 300-3532 color range share an identical HDPE thread specification — color is the only variable across the 14-color lineup.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers and saline | Excellent |
| Dilute acids and bases | Excellent |
| Alcohols (ethanol, isopropanol) | Good |
| Many organic solvents | Good — verify for extended contact |
| Chlorinated / aromatic solvents | Not recommended for prolonged exposure |
| Cryogenic storage (–80°C) | Compatible |
| Autoclaving (121°C / 15 psi) | Compatible |
Quality & Procurement
Made in USA, these Caplugs® Evergreen screw caps are produced from BPA-free, phthalate-free HDPE resin under ISO 9001 quality management. The white color was selected specifically to serve biorepository and reference laboratory programs where label readability is a primary workflow requirement. LabSupplies.com is an authorized Caplugs® Evergreen dealer shipping from USA inventory, with tiered volume pricing available for institutional purchasers, hospital systems, and grant-funded research programs.
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 compatible only with Caplugs® Evergreen 20 mL screw-neck vials and 30 mL centrifuge tubes. Always confirm your tube format before ordering.
Are these caps suitable for –80°C biorepository storage?
Yes. HDPE maintains dimensional stability and a secure threaded seal at –80°C, making these caps suitable for long-term frozen archiving. The white surface also provides optimal contrast for cryogenic adhesive labels commonly used in biorepository programs.
Are the caps sterile, and can they be autoclaved?
The caps are supplied non-sterile. However, they are autoclave-compatible at 121°C / 15 psi, so they can be sterilized in-house prior to use in aseptic workflows if required.
Why choose white caps over other colors in the 300-3532 range?
White provides the highest-contrast printing surface for adhesive labels and LIS-generated barcodes, making it the preferred choice for biorepository programs and reference laboratories where specimen identity is carried on the label rather than communicated by stopper color alone. All colors in the 300-3532 lineup share the same HDPE formulation and thread specification — white is the optimal choice when label legibility is the priority.