Caps, Screw Top, with Soft-Guard, White Silicone Rubber / Red PTFE Septa, bonded in "knurled", polypropylene, Blue Caps. For use with 9-425mm thread, 12x32mm autosampler vials. Soft-Guard Brand. 100/PK
Screw caps are widely used autosampler vial closures designed to provide consistent sealing, ease of use, and broad compatibility across chromatography workflows. This subcategory includes screw caps with a range of septa materials, cap colors, and thread configurations suitable for HPLC, LC‑MS, GC, and GC‑MS applications.
Screw caps deliver reliable sealing performance when properly matched to vials with the same thread design and thread pitch, helping to prevent leaks, evaporation, and misalignment during injection. Correct cap‑to‑vial matching is essential for maintaining sample integrity and ensuring reproducible analytical results.
This category includes multiple screw‑cap product lines developed to address different laboratory needs:
Soft‑Guard™ screw caps, designed to provide smooth needle penetration and reliable resealing
BASIK™ screw caps, intended for general laboratory applications where economic performance is appropriate
MICROSOLV™ brand screw caps, commonly used in pharmaceutical and validated workflows
AQ™ and AQR™ screw caps, formulated for LC‑MS and GC‑MS methods requiring exceptionally low extractable levels
Screw caps are available with pre‑slit and non‑slit septa options, supporting compatibility with a variety of autosampler designs and injector requirements. Selection of cap type and septum configuration should be based on analytical sensitivity, injection frequency, and instrument compatibility.
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