CUSTOM ITEM: Caps, Screw Top, with Silicone Rubber / PTFE Pre-Slit Septa, bonded in "knurled", polypropylene, Black Caps. For use with 13-425mm thread, 15x45mm autosampler vials. MICROSOLV Brand. BULK PRICING.

Additional Info:

Screw caps provide a secure, threaded sealing solution that ensures consistent and leak‑resistant performance in autosampler applications. The knurled polypropylene design allows for easy handling and reliable tightening for repeatable sealing.

The 9504S‑30C‑BK Screw Caps feature bonded silicone/PTFE pre‑slit septa designed to reduce needle resistance and improve penetration consistency. The pre‑slit construction increases the effective needle strike area, making these caps particularly useful for autosamplers where accurate alignment is critical.

These caps are commonly recommended for older Waters® autosampler systems, where pre‑slit septa can help improve injection consistency and reduce needle wear. The PTFE layer provides chemical resistance and sample protection, while the silicone backing offers resealing capability for multiple injections.

Designed specifically for 15 × 45 mm, 4 mL autosampler vials, these caps support both analytical workflows and routine laboratory use. The black polypropylene cap is suitable for light‑sensitive samples and organized workflow identification.


Key Features & Benefits

  • Pre‑slit septa ✅ Easier needle penetration and reduced resistance

  • Silicone/PTFE construction ✅ Chemical resistance and sample protection

  • Bonded septa ✅ Secure fit and consistent performance

  • Threaded screw cap ✅ Leak‑resistant, reliable sealing

  • Knurled cap design ✅ Easy handling and proper tightening

  • Black cap format ✅ Suitable for light‑sensitive samples


Typical Applications

  • HPLC and UHPLC analysis

  • LC‑MS workflows

  • Older Waters® autosampler systems

  • GC and routine analytical applications

  • Use with 4 mL (15 × 45 mm) autosampler vials


Important Notes

  • For 13‑425 thread, 15 × 45 mm autosampler vials only

  • Pre‑slit septa improves penetration but may reseal less effectively than non‑slit septa

  • Suitable for multiple injections depending on method requirements

  • Designed for compatibility with legacy autosampler systems

  • This and other custom items are Custom Ordered and require quotation


Additional Resources


Custom Item Pricing Information


Custom Order Item. Inquire for more information.

© Copyright 2026. MICROSOLV. All Rights Reserved. Website & Hosting by BlueTone Media