MST™ Flat-Top Cryogenic Vial Caps — HDPE, Red, 200/Bag (300-3910-FR20)
These red high-density polyethylene flat-top caps are purpose-built for MST™ cryogenic vials, rated for storage at -80°C mechanical freezers, liquid nitrogen vapor phase, and full LN₂ immersion down to -196°C. Supplied 200 per bag, part number 300-3910-FR20 carries the flat-top profile that improves stacking density in cryo boxes and provides a consistent surface for robotic cap-handling systems. Red follows the CLSI H3 red-top serum convention, making these caps the standard choice for designating serum-derived aliquots and no-additive biobank specimens within MST™ cryo archives.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3910-FR20 |
| Sub-Brand | MST™ (Caplugs® Evergreen) |
| Cap Profile | Flat Top |
| Material | High-Density Polyethylene (HDPE) |
| Color | Red |
| Cryogenic Rating | LN₂ vapor phase and immersion (-196°C) |
| Ultra-Low Temperature Storage | -80°C compatible |
| Autoclave Compatibility | 121°C / 15 psi |
| Pack Size | 200/Bag |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Country of Origin | USA |
Applications
- Serum-derived aliquot archiving in biobanks, where red follows the CLSI H3 red-top serum convention for immediate specimen identification
- Long-term cryogenic storage at -80°C mechanical freezers and liquid nitrogen vapor-phase repositories at -196°C
- High-density cryo box programs where flat-top caps maximize stacking efficiency compared to dome-top designs
- Automated robotic cryo vial handling lines requiring a flat, uniform cap surface for consistent mechanical engagement
- Color-coded multi-specimen cryo box organization across large biorepository programs
- Replacement supply for lost or damaged caps on existing MST™ cryogenic vials
Compatibility
These caps are designed exclusively for MST™ cryogenic vials and are not interchangeable with CryoSure® vials, which use a different thread and dome-top profile. The flat-top geometry of the MST™ series is a deliberate design distinction — it improves stacking density and supports robotic handling in a way that dome-top caps cannot. When transitioning from OEM or alternate-brand caps, validate fit with a sample lot before committing to bulk purchase, as thread specifications are specific to the MST™ vial series.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Liquid nitrogen (-196°C) | Excellent — engineered for LN₂ vapor phase and immersion |
| Storage at -80°C | Excellent — HDPE cryo-toughened |
| Aqueous cryoprotectants | Excellent |
| DMSO (5–10% cryo media concentrations) | Good |
| Autoclave (121°C / 15 psi) | Compatible |
| Concentrated organic solvents | Not recommended |
Quality & Procurement
Made in USA, these MST™ caps are manufactured by Caplugs® Evergreen from BPA-free, phthalate-free HDPE resin engineered to maintain structural integrity across the full cryogenic range from LN₂ immersion at -196°C through autoclave sterilization at 121°C. LabSupplies.com is an authorized Caplugs® Evergreen dealer shipping from USA inventory, with tiered pricing available for high-volume biobank programs, hospital systems, and grant-funded research institutions.
Frequently Asked Questions
Will these caps fit my CryoSure® cryogenic vials?
No — MST™ caps use a thread and flat-top profile specific to MST™ vials. CryoSure® vials use a different thread and dome-top cap design. Always match cap series to vial series, and validate fit with a sample before bulk purchase.
Are these caps rated for direct liquid nitrogen immersion?
Yes. The HDPE used in these caps is rated for both LN₂ vapor-phase storage at -196°C and full liquid nitrogen immersion, as well as routine -80°C mechanical freezer storage.
Can these caps be autoclaved before use?
Yes. HDPE is compatible with standard autoclave cycles at 121°C / 15 psi, allowing sterilization before filling cryogenic vials with biological specimens.
Why are there 12 MST™ cap colors, and when should I use red?
The MST™ series offers 12 colors for color-coded specimen routing and cryo box organization across large biorepository programs. Red specifically mirrors the CLSI H3 red-top convention, making it the standard designation for serum-derived cryogenic aliquots and no-additive biobank specimens so laboratory staff can identify specimen type at a glance without relabeling.