Both systems are designs holes machined into the handguard instead of to said rail. How they work differs from your typical Picatinny rail, though plenty of M-LOK and KeyMod handguards have a Picatinny rail as well. Or this barreled upper from Palmetto State Armory with KeyMod handguard: PSA complete upper with KeyMod handguard. Both M-LOK and KeyMod handguards are lightweight and provide a more comfortable hold on the gun without a cheese grater effect on the support hand.Īdditionally, some companies sell uppers or complete guns with M-LOK or KeyMod handguards, such as this DDM4 V7 Pro with an M-LOK handguard from Daniel Defense: Daniel Defense rifle with M-LOK handguard. Lots of gun owners prefer these to traditional quad rail. Or this KeyMod rails handguard, also by Leapers: KeyMod handguard by Leapers, Credit: Daniel Defense Quad Rail Handguard, Courtesy Brownells Midwest Industries M-LOK handguard, Courtesy Midwest Industries