Comp-N-Choke Non-Ported ARC Series Stainless Choke Tube for 12 Gauge Krieghoff.
 
Steel Shot Safe Up To And Including Improved Modified.
 
Extended choke with extensively-tested design for improved patterning. Conical/parallel internal configuration.
Two large constriction markings on extended portion for easy identification.

Easy to install and remove with your fingers. No special wrench or tool required.
 
If you don't see what you're looking for in my store, contact me and I'll get it for you.