12.7 mm (1/2″) OD Marathon long-life center guide GC septa PK24.

Marathon long-life GC Septa

This is an advanced GC septum for autosampler use, with significantly longer life. The CRS Marathon GC septum typically achieves 400 injections without failure when used with a rounded-tip (HP-style) needle and autosampler or needle guide. Now you can make extended autosampler runs without fear of sample loss caused by blow-back of leaking carrier gas. The CRS Marathon GC septum is also ideal for standard manual injection GC and GC-MS.