MST™ Recessed-Top Cryogenic Vial Caps — HDPE, Yellow, 200/Bag (300-3914-HY20)
These yellow high-density polyethylene cryogenic vial caps from the Caplugs® Evergreen MST™ line feature a recessed-top profile in which the cap's top surface sits below the outer rim, shielding it from contact damage inside cryo boxes and during routine vial handling. Rated for both liquid nitrogen vapor-phase and immersion storage at –196°C as well as –80°C ULT freezers, part number 300-3914-HY20 is supplied in convenient 200/Bag quantities and is autoclavable at 121°C. The yellow color follows the CLSI H3 SPS/ACD yellow-top convention, making color-coded sample routing straightforward in multi-program biorepositories.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-3914-HY20 |
| Sub-brand | MST™ (Caplugs® Evergreen) |
| Cap Profile | Recessed Top — top surface set below outer rim |
| Material | High-Density Polyethylene (HDPE) |
| Color | Yellow |
| Cryo Rating | LN₂ vapor phase and immersion (–196°C) |
| ULT Freezer Storage | –80°C compatible |
| Autoclave Compatibility | Yes — 121°C / 15 psi |
| Pack Size | 200/Bag |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Country of Origin | USA (California) |
Applications
- Long-term biobank archival storage of biological specimens in liquid nitrogen vapor-phase or immersion conditions
- –80°C ULT biorepository storage of cell lines, serum, plasma, and tissue samples
- DMSO-protected cell line cryopreservation using standard 5–10% cryoprotectant media
- Color-coded sample routing programs where yellow caps indicate CLSI H3 SPS/ACD tube conventions
- High-throughput cryo vial programs requiring an economical cap profile across large inventories
Compatibility
These recessed-top caps are engineered exclusively for MST™ recessed-top cryogenic vials and are not interchangeable with CryoSure® vials or MST™ flat-top vials. Within the MST™ recessed-top format, three colors are available — Natural, Blue, and Yellow — allowing labs to implement a three-tier color-coding scheme without switching vial systems. The recessed-top cap removes completely upon opening, which distinguishes it from the Tethered Recessed profile (300-3918), where the cap remains attached to the vial via a flexible tether after opening. Laboratories already using the MST™ flat-top cap (300-3910) should note that while both caps share the same MST™ vial thread, the top profiles differ and are not cross-compatible as a substitute for each other in programs where top-surface geometry matters for automated cap removal or box stacking.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Liquid nitrogen (–196°C), vapor phase and immersion | Excellent — engineered for LN₂ service |
| ULT storage (–80°C) | Excellent — HDPE cryo-toughened |
| Autoclave (121°C / 15 psi) | Compatible |
| Aqueous cryoprotectants / buffers | Excellent |
| DMSO (5–10% cryoprotectant concentration) | Good — short-term contact at standard cryo media concentrations |
| Concentrated organic solvents | Not recommended |
Quality & Procurement
Made in USA at Caplugs® Evergreen's California manufacturing facility, these MST™ caps are produced from BPA-free, phthalate-free HDPE resin under ISO 9001 quality management. LabSupplies.com is an authorized Caplugs® Evergreen dealer, shipping from USA inventory with tiered volume pricing available for hospitals, biobanks, research institutions, and grant-funded laboratories procuring in case quantities.
Frequently Asked Questions
Will these caps fit CryoSure® vials or MST™ flat-top vials?
No. MST™ recessed-top caps are designed specifically for MST™ recessed-top cryogenic vials. They are not interchangeable with CryoSure® vials, and while MST™ flat-top vials share the same thread, the differing top-profile geometry means the two cap styles are not substitutes for each other within a recessed-top program.
Are these caps safe for liquid nitrogen immersion storage?
Yes. The HDPE formulation used in MST™ caps is engineered to remain impact-resistant and maintain a secure seal through both LN₂ vapor-phase (–196°C) and direct immersion conditions, as well as routine –80°C ULT freezer storage.
Can these caps be autoclaved before use?
Yes. The HDPE construction is autoclave-compatible at the standard 121°C / 15 psi cycle, making these caps suitable for workflows that require sterile-starting consumables such as cell line banking.
What is the difference between the recessed-top cap and the tethered recessed cap?
When opened, the recessed-top cap (300-3914-HY20) separates completely from the vial. The tethered recessed cap (300-3918) stays physically attached to the vial via a flexible tether after opening, which reduces the risk of cap loss or mix-up in high-throughput retrieval workflows. Both share the same recessed-top profile and MST™ vial thread.