4 mL Sample Cup Caps — Flat Top, LDPE, Natural, 1000/Bag (300-1006-020)
These natural Low-Density Polyethylene (LDPE) flat top caps are the standard sealed closure for Caplugs® Evergreen 4 mL round-bottom sample cups used in urinalysis, clinical chemistry, and serology workflows. Part number 300-1006-020 snaps onto the sample cup rim with positive retention, forming a complete sealed closure that prevents evaporation during refrigerated storage, pneumatic tube transport, and pre-analytical staging. Supplied non-sterile in convenient 1000/Bag packaging, these caps are sized for high-volume clinical environments where per-cap economy and reliable snap-on performance are both critical.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (MPN) | 300-1006-020 |
| Cap Type | Flat Top |
| Material | Low-Density Polyethylene (LDPE) |
| Color | Natural |
| Cup Compatibility | Caplugs® Evergreen 4 mL round-bottom sample cups |
| Probe Access | No — cap must be removed before probe aspiration |
| Sealing | Full sealed closure |
| Sterility | Non-Sterile |
| Pack Size | 1000/Bag |
| BPA / Phthalates | BPA-free; no phthalate plasticizers |
| Country of Origin | USA (California) |
Applications
- Sealing 4 mL round-bottom sample cups during refrigerated staging and pre-analytical holding
- Urinalysis workflows — capping random urine sample cups through centrifugation and prior to auto-analyzer loading
- Serum and plasma cup storage — preventing evaporation and contamination of primary tube–derived aliquots
- Pneumatic tube transport of capped specimen cups between collection and laboratory areas
- Auto-analyzer sample cup staging (e.g., Cobas® and AU-series discrete analyzers) where cups are capped until aspiration
- General-purpose specimen routing in laboratories that rely on barcode or written labels for identification rather than cap color coding
Compatibility
These caps are designed to fit Caplugs® Evergreen 4 mL round-bottom sample cups (127-0017 family) and are routinely used in clinical workflows that stage capped sample cups on Cobas® and AU-series discrete auto-analyzers before uncapped aspiration. Natural color makes these caps the preferred choice for laboratories that use a secondary labeling system — such as barcode or handwritten ID — as the primary specimen identification method. For color-coded visual routing, compatible alternatives are available in blue (for urine) and red (for serum). Laboratories requiring probe pierce-through access without cap removal should refer to the perforated top cap format instead.
Chemical Resistance
| Reagent / Condition | Compatibility |
|---|---|
| Urine (whole / centrifuged) | Excellent |
| Serum / plasma | Excellent |
| Aqueous buffers and saline | Excellent |
| Standard assay diluents | Excellent |
| Dilute acids and bases | Good |
| Ethanol / isopropanol | Good — short-term contact; not recommended for prolonged immersion |
| Acetone / chlorinated solvents | Not recommended |
Quality & Procurement
Made in USA at Caplugs® Evergreen's California facility, these flat top sample cup caps are produced from BPA-free, phthalate-free LDPE resin under ISO quality manufacturing standards. LDPE's inherent flexibility maintains reliable snap-on retention across the full temperature range of clinical sample handling — room temperature processing, 4°C refrigerated staging, and −20°C frozen storage — without the brittleness that causes rigid plastic closures to fracture under repeated cycling in high-volume labs. LabSupplies.com is an authorized Caplugs® Evergreen dealer and ships from USA inventory, with tiered pricing available for institutional purchasers and grant-funded laboratories.
Frequently Asked Questions
Can the analyzer probe pierce through the cap without removing it first?
No — the 300-1006-020 is a solid flat top cap that requires removal before probe aspiration. Laboratories that require pierce-through probe access should use the perforated top cap format (300-1999-020) instead.
Will these caps hold securely during pneumatic tube transport and centrifugation?
Yes. The LDPE flat top cap snaps onto the sample cup rim with positive retention and maintains that engagement across the temperature and mechanical stresses typical of pneumatic tube transit and low-speed centrifugation steps in clinical pre-analytical workflows.
Why choose natural color instead of blue or red?
Natural (clear/translucent) caps are preferred when laboratories use barcode labels or handwritten IDs as the primary specimen identification method and do not rely on cap color for visual routing. Blue caps conventionally denote urine and red caps denote serum in color-coded workflows; natural is the general-purpose default.
Are these caps compatible with 4 mL flat-bottom sample cups in addition to round-bottom cups?
The source documentation confirms compatibility with Caplugs® Evergreen 4 mL round-bottom sample cups (127-0017 family). If your lab uses flat-bottom cups from a different manufacturer or product line, verify the rim diameter against your cup specification before adopting these caps at scale.