Adapter AK, to be precise AK 47 – AK (new version). Designed for muzzle brake with M24 thread. Standard AK 47 muzzle thread – M14. But nowadays most muzzle brakes having M24 thread.
This adapter is steel nut with slots for retaining pin which is located on the front sight body. M14 is internal left-hand thread; M24 – external.
Muzzle adapter installation sequence:
1. Remove standard muzzle brake;
2. Mount the adapter, screw it all the way and secure with the pin;
3. Mount muzzle brake or tactical flash cover and secure it with the pin.