Updated return spring mechanism for the Zenit B-33 dust cover.

Rear segment made to be compatible with B-33 dust cover (may not work with standard dust cover), front segment's rear section filed down for flat surface to avoid the bolt carrier getting stuck in the rear position. 

Replacement part for loss/incomplete kits/old B-33 kits.

Installed on your standard return spring in place of the standard return mechanism.

B-33 Return Spring Mechanism