Embedding Cassettes, PP, Natural, Thermo Fisher® Compatible — 258-4045-030 | 500/Bag | Caplugs® Evergreen

Embedding Cassettes with Stainless Steel Covers, Polypropylene (PP), Natural — 500/Bag Unassembled

Technical Narrative

The Caplugs® Evergreen 258-4045-030 is a Polypropylene (PP) tissue embedding cassette with a stainless steel cover — the preferred configuration for high-throughput surgical pathology laboratories where plastic cover float-out, warping, or loss in automated tissue processor baskets is a recurring workflow disruption. The stainless steel cover provides the mass, rigidity, and mechanical engagement required to remain positively locked on the PP cassette base throughout automated tissue processor agitation cycles, preventing the cover-detachment events that interrupt processing runs, contaminate processor baths, and compromise specimen integrity. Supplied unassembled 500/Bag for pre-labeling flexibility.

The PP cassette body withstands the full histology processing chemical sequence — 10% NBF formalin fixation, graded ethanol dehydration, xylene or xylene substitute clearing, and paraffin wax infiltration at 56–65°C — without warping, cracking, or dimensional change that would compromise embedding orientation or block face geometry. The natural PP body accepts pencil, ballpoint pen, and laser engraving for specimen identification directly on the cassette body, reducing the label loss risk associated with adhesive label cassette identification during processor agitation.

At $45.19 per 500/Bag — $0.0904 per cassette-and-cover pair — the delivers stainless steel cover security at a per-unit cost competitive with standard plastic-cover cassettes for high-volume surgical pathology programs where cover integrity directly impacts processing throughput and specimen safety.

Technical Specifications — Caplugs® Evergreen

Tissue Processing & Embedding Workflow Compatibility —

The PP cassette with stainless steel cover is compatible with standard histology tissue processing and embedding workflows:

Stainless steel covers lock onto PP cassette bases with positive engagement. Confirm cover-to-base fit on your specific processor basket configuration with a sample set before bulk purchase.

Chemical & Processing Compatibility — Polypropylene (PP)

PP body with stainless steel cover provides full histology processing solvent compatibility — paraffin wax, xylene, ethanol series, formalin, and most decalcification reagents.

Not autoclave-compatible for cassette sterilization — histology cassettes are used with formalin-fixed non-sterile tissue and do not require sterilization before use.

Anatomic Pathology Laboratory Applications

The embedding cassette with steel cover serves high-volume hospital and reference anatomic pathology laboratories processing surgical biopsy, excisional, and resection specimens through automated tissue processors; gastrointestinal and endoscopy pathology programs with high-throughput mucosal biopsy processing; prostate and genitourinary pathology programs; academic medical center surgical pathology cores; and any pathology setting where plastic cover float-out or loss in tissue processor baskets is a documented workflow problem.

U.S. Manufacturing, Quality & Institutional Procurement

Every Caplugs® Evergreen lot is precision-molded at our California manufacturing facility and subject to rigorous dimensional inspection and material purity verification. We supply hospital systems, reference laboratories, and federal procurement offices under institutional pricing programs with blanket-order support and same-day shipping on stocked inventory. Request a compatibility sample below to validate fit with your processor configuration before committing to volume.

Frequently Asked Questions — Caplugs® Evergreen

Why use a stainless steel cover instead of a standard plastic cover?

Stainless steel covers provide mechanical engagement with the PP cassette base that prevents the float-out and cover-loss events common with lighter plastic covers during automated tissue processor agitation, particularly in rapid-cycle processors running aggressive solvent agitation sequences. Lost plastic covers contaminate processor baths, interrupt processing runs, and require time-consuming bath cleaning. The steel cover eliminates this failure mode while remaining fully compatible with the histology processing solvent sequence.

Is the compatible with all automated tissue processors?

The PP cassette body is compatible with all standard automated tissue processors including Leica ASP300S/ASP6025, Thermo Fisher Excelsior ES/AS, and Sakura Tissue-Tek VIP 6. Confirm that the steel cover height clearance fits your specific processor basket and retainer bar configuration before large-volume purchase — cassette basket retainer bar heights vary between processor models and can limit cover height compatibility.

Are the cassettes BPA-free?

Yes. The PP cassette body is molded from virgin Polypropylene containing no BPA and no phthalate plasticizers. The stainless steel cover is inert and contains no polymer additives.