9/17/21 - This is a very nice Heckler & Koch HK4 in the original box, and comes with a conversion kit for both .22LR and 9mm. This one was made in July of 1971, so C&R eligible. The HK4 is basically a new version and a more refined development of the Mauser HSc self-loading pistol. Heckler & Koch was familiar with HSc design, as during pre-war and post-war periods, many of the Heckler & Koch company founders were employees of the Mauser-Werke Oberndorf A.G. company. This example falls in the range of a West German Police contract order, one of about 12,000 produced. It has a bit of muzzle wear on both sides, maybe a few minor surface scratches on the front grip strap. The conversion kits aren't numbered to the gun but all have excellent bores.