F.A.B. Defense AK-47 Quad Rail Handguard, Fits AK-47, Polymer, Black FX-AK47B The AK-47 is a light and durable quad-rail polymer handguard system for the AK 47 platform. It enables four picatinny rails for mounting of reflex sights" foregrips" bipods or any other 1913 picatinny based accessory.