This Heckler & Koch SP5 pistol is based largely on the Navy version of the MP5 submachine gun. This version includes the threaded tri-lug adapter at the muzzle, a paddle-style magazine release paired with the push-button release, and an ambidextrous selector switch. Otherwise, this SP5 includes many of the same features and controls as its select-fire cousin.
Since this is sold commercially as a semi-auto-only, non-NFA, large-format pistol, the Heckler & Koch SP5 does not include a stock or stabilizing brace with the gun. Instead, a polymer cap at the receiver is topped by a mounted sling swivel, which pairs with the elastic retention strap that ships with the gun. When wearing the elastic strap, shooters can stabilize the platform by driving the pistol out in front of their chest, which puts tension on the strap and helps to minimize recoil and muzzle rise.
To take a closer look at the Heckler & Koch SP5 pistol and see it perform on the range, check out American Rifleman's "New for 2021" feature video above.