50 mL Centrifuge Tube Screw Caps — HDPE, Blue, Non-Sterile, 1000/Bag (300-3541-B20)
These replacement screw caps are designed to fit standard 50 mL centrifuge tubes, molded from high-density polyethylene (HDPE) in a distinctive blue color for quick visual identification. Supplied non-sterile in bulk (1000/Bag), part number 300-3541-B20 is well suited for high-throughput laboratories that routinely replace, restock, or color-code tube closures. The rigid HDPE construction provides a secure, leak-resistant seal for everyday sample storage and centrifugation workflows.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3541-B20 |
| Intended Tube Size | 50 mL Centrifuge Tube |
| Closure Type | Screw Cap |
| Material | High-Density Polyethylene (HDPE) |
| Color | Blue |
| Sterility | Non-Sterile |
| Pack Size | 1000/Bag |
| Country of Origin | USA |
Applications
- Replacing lost or damaged caps on 50 mL centrifuge tubes in routine laboratory workflows
- Color-coded sample organization and tube identification across multiple studies or sample sets
- Bulk restocking of centrifuge tube closures for high-volume clinical and research environments
- Secure capping of tubes during low- to moderate-speed centrifugation and sample storage
- General specimen and reagent containment in biological, chemical, and environmental labs
Material & Chemical Resistance
High-density polyethylene offers broad resistance to aqueous solutions, dilute acids and bases, and many common laboratory reagents, making it a reliable choice for general sample storage and handling. HDPE is more rigid than low-density polyethylene and maintains its shape under normal screw-cap torque. Note that HDPE is not recommended for autoclave sterilization, and compatibility should be verified before use with concentrated oxidizing acids, aromatic solvents, or halogenated solvents.
Quality & Procurement
Made in USA, Caplugs® Evergreen screw caps are manufactured under ISO 9001 quality management from BPA-free, phthalate-free, latex-free resin. LabSupplies.com is an authorized dealer and ships from USA inventory, typically same business day for stocking items, with tiered pricing available for institutional and grant-funded laboratories.
Frequently Asked Questions
Are these screw caps sterile?
No — they are supplied non-sterile in 1000/Bag bulk packaging. Laboratories requiring sterile closures should consider a separate sterilization step or select a sterile product offering.
Can these caps be autoclaved?
HDPE is generally not recommended for autoclave sterilization, as the elevated temperature and steam pressure can distort the material. For applications requiring sterile closures, chemical sterilization or gamma-irradiated alternatives should be considered.
What chemical types are compatible with HDPE screw caps?
HDPE performs well with aqueous samples, dilute acids and bases, and many common buffers and biological reagents. Compatibility should be verified before use with concentrated oxidizing acids, aromatic solvents, or chlorinated solvents, which can degrade polyethylene.