Material:CNC 6061 Aluminium Weight:212 g This aluminium Railed Top Cover is made by precision CNC machines and has matt black hardcoat-anodized finishing.It fits AKM(T.Marui GBB) only.This handguard must be installed above our AKM Alpha 6" handguard (i.e. item No.2400) or Alpha 10" handguard (i.e. item No.2401).The top of Cover has a Picatinny Rail which does not overlap the line of original standard mechanical sights. All products are made for airsoft only.They are not made for real steel firearms