KF-40 PTFE Centering Ring

These KF40 centering rings have a PTFE (teflon) inner centering ring and Viton (FKM) o-ring.

Centering rings are used to mostly in vacuum systems to connect to other KF or ISO flanges.

PTFE can handle high temperatures up to 250°C, is chemical resistant to nearly all chemicals, doesn't corrode, and can act as an electric insulator between other metal KF parts. 

The o-rings have been cleaned and baked out before shipping.

Maximum bakeout temperature is 200 °C (limited by the the o-ring).

Other o-ring materials available upon request. 

Silicone, FFKM (kalrez), low outgassing viton, etc