The Vism AKM Fixed MILSPEC STK Tube is a non-folding adapter for ak variants.It mounts onto akm pattern stamped receivers with square cut flat rear receiver section.The tube allows a variety of ar style mil-spec collapsible buttstocks to be installed onto an ak variant.It features qd sling mounts on both sides of the stock adapter.The stock tube is hollow with a rubber end plug and it can be used to store parts and cleaning tools.