MST™ Flat-Top Cryogenic Vial Caps — HDPE, Amber, 200/Bag (300-3910-FN20)
These Caplugs® Evergreen MST™ flat-top cryogenic vial caps are molded from high-density polyethylene (HDPE) in amber and supplied 200 per bag for biobank, ultra-low temperature, and liquid nitrogen archive workflows. Rated for LN₂ vapor-phase and immersion storage at -196°C as well as -80°C mechanical freezer use, the amber HDPE construction provides partial UV and visible-light attenuation — protecting semi-photosensitive specimens without fully obstructing visual inspection of vial contents. Part number 300-3910-FN20 is an MST™-exclusive color and fits MST™ cryogenic vials only; it is not interchangeable with CryoSure® vials, which use a different thread and dome-top cap profile.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3910-FN20 |
| Sub-brand | MST™ (Caplugs® Evergreen) |
| Cap Profile | Flat Top |
| Material | High-Density Polyethylene (HDPE) |
| Color | Amber |
| Cryo Rating | LN₂ vapor phase and immersion (-196°C) |
| Low-Temp Storage | -80°C and -196°C compatible |
| Light Attenuation | Partial UV/visible — amber HDPE reduces light transmission |
| Autoclavable | Yes (121°C / 15 psi) |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Pack Size | 200/Bag |
| Country of Origin | USA (California) |
Applications
- LN₂ vapor-phase biobank archiving at -196°C for long-term biological specimen storage
- -80°C ultra-low temperature mechanical freezer repositories in clinical, research, and pharmaceutical settings
- Semi-photosensitive specimen storage where partial UV and visible-light attenuation is required but full opacity is not
- Color-coded cryogenic box organization — amber provides a visually distinct routing color across multi-specimen programs
- High-density cryo box stacking programs that benefit from the flat-top profile over dome-top alternatives
- Automated and robotic cryogenic vial handling lines where a consistent flat cap profile ensures reliable engagement
- Replacement cap supply for existing MST™ vial inventories with lost or damaged original caps
Compatibility
These caps are designed exclusively for MST™ cryogenic vials and are not interchangeable with CryoSure® vials, which use a different thread form and dome-top cap geometry. The flat-top profile distinguishes MST™ caps from the CryoSure® dome-top line throughout the Caplugs® Evergreen range. Amber and Chocolate are the two MST™-exclusive colors — neither is offered in the CryoSure® lineup. If complete light blockage is required, the Black MST™ cap is the appropriate specification choice; for applications where some visual inspection of vial contents must be retained alongside light protection, the amber cap provides the intermediate option. Validate fit using a sample lot before committing to large-volume procurement, particularly when capping vials sourced from existing inventory.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Aqueous buffers / saline | Excellent |
| Dilute acids and bases | Good |
| Alcohols (e.g., ethanol, isopropanol) | Good — short-term contact; verify for prolonged exposure |
| Liquid nitrogen / cryogenic conditions | Excellent — rated to -196°C |
| Chlorinated solvents (e.g., chloroform, DCM) | Not recommended |
| Aromatic solvents (e.g., toluene, xylene) | Not recommended |
| Autoclave (121°C / 15 psi) | Compatible |
Quality & Procurement
Made in USA at Caplugs® Evergreen's California manufacturing facility, these MST™ vial caps are produced from BPA-free, phthalate-free HDPE resin under ISO 9001 quality management standards. LabSupplies.com is an authorized Caplugs® Evergreen dealer and ships from USA inventory, with tiered volume pricing available for biobanks, hospitals, research institutions, and other high-throughput procurement programs.
Frequently Asked Questions
Will these caps fit CryoSure® cryogenic vials?
No — MST™ flat-top caps use a thread and cap profile specific to MST™ vials and are not interchangeable with CryoSure® vials. Always validate fit with a sample before switching from OEM or other cap supply.
How much light protection does the amber color actually provide?
Amber HDPE reduces UV and visible-light transmission to the vial contents — more protection than a clear cap, but less than a fully opaque black cap. Amber is the conventional choice when partial attenuation is sufficient and some ability to visually inspect vial contents is still desired. For complete light blockage, specify the Black MST™ cap instead.
Are these caps rated for liquid nitrogen immersion, or only vapor phase?
Both — the 300-3910-FN20 is rated for LN₂ vapor-phase storage at -196°C as well as direct LN₂ immersion, and is also compatible with -80°C mechanical freezers.
Can these caps be autoclaved before use?
Yes. HDPE MST™ caps are autoclavable at 121°C / 15 psi, making them suitable for sterile workflow preparations where autoclaving is required prior to capping.