Selling a hk usc 45 acp carbine convertered to ump via hdps stock block with hdps rails. Has FBI UMP (semi/safe) lower housing that accepts real ump double stack mags,hdps 16 inch barrel made to ump 45 specs and also shimmed to take single stack mags as well. Comes with one 25, one 15, four 20, and original 10 round mags. Only trade I'm taking is a bushmaster acr in fde, text 214-616-7200for any questions.