1.0 mL Microcentrifuge Tube Stopper Caps — HDPE, Natural, 1000/Bag (300-3710-020)
These natural HDPE plug-in stopper caps provide a reliable friction-fit closure for standard 1.0 mL microcentrifuge tubes, making them an everyday workhorse for molecular biology, biochemistry, and clinical aliquoting workflows. Supplied non-sterile in 1000/Bag bulk packaging, the rigid high-density polyethylene construction delivers consistent retention in the small-diameter openings characteristic of the 1.0 mL tube format. Natural coloring serves as the all-purpose default for any lab labeling or color-coding system.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3710-020 |
| Tube Format | 1.0 mL microcentrifuge tubes |
| Cap Style | Stopper — plug-in friction fit |
| Material | High-Density Polyethylene (HDPE) |
| Color | Natural |
| Sterility | Non-Sterile |
| Pack Size | 1000/Bag |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Country of Origin | USA |
Applications
- General 1.0 mL microcentrifuge tube capping during routine sample preparation and processing
- Pellet and supernatant storage between centrifuge spins requiring brief refrigerated holds
- Reusable closure for enzyme, antibody, and oligonucleotide aliquots in 1.0 mL tubes
- Biobank and biorepository archiving of small-volume 1.0 mL specimens under refrigerated conditions
- Pre-PCR and pre-qPCR sample hold before transfer to a PCR plate
- Serum and plasma clinical chemistry aliquots requiring a sealed closure during secondary test transit
- Color-coded batch routing when used alongside the green sibling cap (300-3710-G20) to designate sample type or processing batch
- Low-cost replacement for lost or damaged integral hinge-caps on existing 1.0 mL tube stock
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / serum / plasma | Excellent |
| Short-chain alcohols (brief contact) | Good |
| DMSO (≤10%) | Good |
| Storage at −20 °C / −80 °C | Suitable — HDPE cryo stability |
| Autoclave (121 °C) | Compatible |
| Concentrated organic solvents | Not recommended |
Quality & Procurement
Made in USA, these Caplugs® Evergreen stopper caps are manufactured from BPA-free, phthalate-free HDPE resin under ISO 9001 quality management. LabSupplies.com is an authorized dealer and ships from USA inventory, with same-business-day fulfillment typically available for stocking items. Tiered volume pricing is available for high-throughput labs, biobanks, and institutional procurement programs. Before committing to bulk quantities, we recommend validating stopper-to-tube fit with a sample lot against your specific tube brand and lot.
Frequently Asked Questions
Will these stoppers fit any brand of 1.0 mL microcentrifuge tube?
These caps are designed for the standard 1.0 mL microcentrifuge tube opening diameter found in HDPE and PP tubes from most major manufacturers. Because minor dimensional variation exists between tube brands and lots, it is good practice to verify the friction-fit retention with a small sample before placing a high-volume order.
Are these stopper caps autoclavable?
Yes — HDPE is compatible with standard autoclave conditions (121 °C), so these caps can be sterilized alongside tubes when sterile closure is required for your workflow.
What is the difference between the natural cap and the green sibling option?
Both the natural (300-3710-020) and green (300-3710-G20) caps share identical HDPE construction and stopper geometry. The only difference is color. Using two colors allows labs to visually route sample types or processing batches without relabeling individual tubes.
Are these caps supplied sterile?
No — they are supplied non-sterile in 1000/Bag bulk packaging. For applications requiring sterile closures, autoclave the caps prior to use or contact LabSupplies.com to inquire about sterile packaging options.