Polymer Dual Coupler adjustable Fits 5.56 and 7.62 Magazines For AK47 M4 The coupler which allows the user to attach two magazines together for more efficient speed reloads.The features a two-piece bolt on design and durable， lightweight reinforced polymer construction.Features: Fits 5.56 and 7.62 magazines. Impact resistant polymer construction provides light weight and resists operational abuse. Wide-set， two-piece bolt-on design resists flexing. Integral grooves interface with ribbing to eliminate slippage