Caplugs® Evergreen 21 mL Round Bottom Test Tubes with Blue Screw Caps, 16 x 150 mm, Polystyrene, Natural, 1000/Bag
The Caplugs® Evergreen 21 mL Round Bottom Test Tubes deliver clear, crack-resistant polystyrene tubes in a 16 x 150 mm format with leak-resistant blue screw caps, ideal for sample collection, serial dilutions, and routine clinical and diagnostic handling. Each tube offers excellent optical clarity for visual inspection and turbidity reads. Shipped unassembled, this bulk 1000/Bag pack suits high-throughput benches.
Technical Specifications
| Product Type | Round Bottom Test Tubes (with Screw Caps) |
|---|---|
| Volume/Size | 21 mL; 16 x 150 mm |
| Material | Polystyrene (PS), Natural |
| Closure/Cap | Blue Screw Cap (supplied unassembled) |
| Sterility | Non-Sterile |
| Pack Size | 1000/Bag |
| Country of Origin | USA |
Applications
- Routine sample collection and short-term specimen storage
- Serial dilutions and reagent preparation at the bench
- Visual turbidity and colorimetric reads requiring clear walls
- Clinical and diagnostic aliquoting in screw-capped tubes
- General chemistry and microbiology workflow staging
- High-throughput tube handling in rack-based batches
Quality & Procurement
labsupplies.com is an authorized Caplugs® Evergreen dealer shipping from US inventory, with these tubes Made in USA. Bags carry lot numbers to support traceability for CAP-, CLIA-, and ISO 15189-accredited laboratories. Institutional and grant-funded tiered pricing is available for bulk and standing orders.
Frequently Asked Questions
Are these test tubes sterile?
No. These tubes are non-sterile and are intended for general laboratory use. For applications requiring sterility, validate an appropriate decontamination method compatible with polystyrene.
Do the tubes ship with caps attached?
The tubes ship unassembled, meaning the blue screw caps are packed separately within the 1000/Bag pack rather than pre-fitted, so you cap them as needed at the point of use.
What are the tube dimensions and capacity?
Each tube measures 16 x 150 mm with a round bottom and a nominal capacity of 21 mL, a standard format that fits common 16 mm tube racks and instrument carriers.
Is polystyrene suitable for my reagents?
Polystyrene offers excellent clarity and rigidity but has limited resistance to many organic solvents. Confirm reagent compatibility with PS before use; for aggressive solvents, choose a polypropylene tube instead.