2-Compartment Acetal (POM) Biopsy Cassettes with Covers, 0.6 mm Holes, White — 500/Bag
These white acetal (POM) biopsy cassettes feature two isolated integral compartments with 0.6 mm holes per compartment, designed to maintain site-specific tissue identity through the complete histology workflow — from formalin fixation and xylene-based tissue processing through paraffin infiltration and sectioning. Supplied unassembled as 500 cassettes plus 500 covers per bag, part number 258-4252-W90 is the standard choice for bilateral needle core biopsies and two-site endoscopic biopsy panels where inter-compartment specimen separation is a diagnostic requirement.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 258-4252-W90 |
| Compartments | 2 isolated compartments — integral molded dividers |
| Material | Acetal (POM) — Polyoxymethylene |
| Color | White |
| Hole Size | 0.6 mm per compartment |
| Xylene Resistance | Excellent |
| Paraffin Compatibility | Excellent — dimensional stability at 56–65°C |
| Formalin Compatibility | Excellent (10% NBF, extended exposure) |
| Assembly State | Unassembled — 500 cassettes + 500 covers per bag |
| Sterility | Non-Sterile |
| Pack Size | 500/Bag |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Country of Origin | USA (California) |
Applications
- Bilateral prostate needle core biopsies — right and left lobe cores preserved and processed in a single cassette while maintaining discrete site identity
- Two-site endoscopic biopsy panels requiring unambiguous compartment-to-compartment specimen segregation through the full processing sequence
- Any multi-site biopsy protocol where reducing cassette count per patient case without sacrificing specimen traceability is a workflow priority
- Small-fragment histology specimens requiring the enhanced retention of a 0.6 mm aperture relative to standard 1.0–2.0 mm cassette hole sizes
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| 10% Neutral buffered formalin (NBF) | Excellent — extended exposure |
| Xylene (clearing agent) | Excellent — POM maintains aperture geometry under prolonged immersion |
| Graded alcohols (dehydration series) | Excellent |
| Paraffin infiltration at 56–65°C | Excellent — dimensional stability through repeated thermal cycling |
| Aqueous buffers / saline | Excellent |
Quality & Procurement
Made in USA (California), these Caplugs® Evergreen cassettes are manufactured from BPA-free, phthalate-free acetal (POM) resin selected specifically for its crystalline dimensional stability at sub-millimeter aperture sizes — ensuring the 0.6 mm hole geometry is maintained through xylene immersion, processor agitation, and repeated paraffin cycling at 65°C. LabSupplies.com is an authorized Caplugs® Evergreen dealer, shipping from USA inventory with tiered pricing available for high-volume histology labs, hospital pathology departments, and institutional procurement programs.
Frequently Asked Questions
Why are these cassettes made from acetal (POM) rather than polypropylene?
The 0.6 mm hole size demands a polymer with maximum dimensional stability under xylene and thermal cycling. Acetal's crystalline POM structure maintains aperture geometry through prolonged xylene immersion and repeated paraffin infiltration at 65°C — a level of stability that polypropylene cannot consistently deliver at sub-millimeter aperture sizes, where any polymer creep or hole deformation directly compromises specimen retention.
Are the compartment dividers removable?
No. The two dividers are molded as integral features of the cassette body, not removable inserts, so inter-compartment specimen isolation is structurally guaranteed through the entire processing solvent sequence.
Are these cassettes compatible with standard automated tissue processors?
Yes. The acetal (POM) construction is chemically resistant to the full reagent series used in automated tissue processors — formalin, graded alcohols, xylene, and paraffin at 56–65°C — and the cassette dimensions are consistent with standard processor baskets and embedding molds.
Do these cassettes come pre-assembled with covers attached?
No — the bag contains 500 cassettes and 500 covers packed unassembled. Covers are snapped onto cassettes at the point of use, which is standard practice for biopsy accessioning workflows.