Contemporary HK polymer-frame pistols follow an evolutionary pattern. The introduction of a new design is followed by a compact version of that design. Some patterns get specialized features like the Expert or Tactical editions. Each version of the HK design is intended for a particular role, and each model seems to prove more refined than the last.
The HK45 (for those who have been living on the moon for the past few years) needs little introduction, but if you must, allow me to introduce it. The Heckler & Koch HK45 is a standard frame 45 ACP handgun born from the culmination of several platforms and circumstances. The HK is derived from the ever-popular HK USP 45 and HK Mark 23, as well as the 1911 (cancelled HK project), as well as a bid for supplying U.S. Special Operations Command (SOCOM).
Many people regard Heckler and Koch as one of the best firearms manufacturers in the world. Their rifles and pistols have earned a reputation for being reliable and sturdy under the harshest of conditions, and have been for longer than even Gaston’s Miracle Pistol. A favorite of the US Navy and law enforcement around the world, the HK USP became synonymous with a no-frills, all business gun, and with its durability and 12-round capacity, it brought a world of .45 ACP hurt to forces looking to increase their ammunition capacity without overloading themselves on weight.