Restek, 21472, Ferrules, Alumaseal, 0.4 mm ID, 10-pk.

Alumaseal ferrules combine the advantages of graphite and Vespel/graphite ferrules, and eliminate the disadvantages, for enhanced performance in any application. The unique front and back ferrule design seals easily and surely, the ferrules will not fragment or off-gas, and they are stable to 550 °C. Alumaseal ferrules will not allow oxygen to permeate into the system, and do not require retightening after temperature cycles, making them ideal for GC-MS applications. They can be used with any standard 1/16" compression-type fitting with fused silica columns. For leak-tight seals, we highly recommend you try Alumaseal ferrules.
Features & Benefits
Aluminum construction—will not crack or fragment.
No retightening required after temperature cycles—excellent for GC-MS.
Eliminate out-gassing and make leak-tight seals for less detector noise.
Unique two-piece design permanently locks on fused silica tubing without causing breakage.
Will not stick in fittings, unlike Vespel or graphite ferrules.
Stable to 550 °C.
Use with any 1/16" compression-type fitting.