Ergo Grip 5-Slot Extended KeyMod U.M.P. Black. The outside is a Picatinny rail. The inside is the mounting system to the Key Mod handguard.Hard anodized finish on 6061 T6 Aluminum Specifications for ERGO KeyMod UMP Picatinny Rail: Manufacturer: ERGO Color: Black Finish: Anodized Fabric/Material: 6061-T6 Aluminum Gun Rail: Picatinny KeyMod Gun Type: Rifle Gun Make: AR Platform Kalashnikov Gun Model: AK-74 AR-10 AK-47 AR-15 Quantity: 1 Features of ERGO KeyMod UMP Picatinny Rail Use your Picatinny accessories on your KeyMod handgaurds with this conversion system. The outside is a Picatinny rail. The inside is the mounting system to the KeyMod handguard. Package Contents: ERGO KeyMod UMP Picatinny Rail Ergo Grip 4766: 5-Slot Extended KeyMod UMP Black