Lesser known but very popular in the 1980s in America were the sporting imports from HK. The SL7 possesses the internals of the HK91, with a three round magazine capacity. About the only recognizable feature of the SL series is the diopter sighting system. The guns are still manufactured for European consumption, but for reasons unknown, are no longer imported into the U.S. Both rifles are equipped with a polygonal bore barrel.