New design AK-74 block fits most ARSENAL CIRCLE 10 5.45x39 mm magazines and will convert them to hold only 10 rounds. The new design features a spring catch which will allow an easy attachment point to the spring. This prevents the block making noise and epoxy can be added at this point to make it permanent. This block will replace the original magazine locking plate. This block and adapter will convert a 45 round Arsenal Circle 10 (5.45x39) magazine to only allow 10 rounds.