Some info from H&K website
The extremely compact HK P7M8 can be drawn, cocked, and fired accurately, faster than any other pistol. With an overall length and width close to many .380 pocket pistols, the full-power 9mm P7M8 has a full-length four-inch barrel enclosed in its low profile steel slide.
The unique HK cocking lever allows the P7M8 to be carried safely with a round in the chamber, yet it is ready to fire by the intentional squeezing of the fingers around the grip. Releasing the cocking lever decocks the P7M8 immediately and renders it completely safe.
The P7M8 gas system retards the movement of the recoiling slide during firing and eliminates the need for a conventional locking mechanism or heavy slide. The low profile slide contributes to the balanced center of gravity and compact size of the P7M8.
Made of high-grade steel, the low profile slide keeps the recoiling mass as small as possible. Combined with the optimal grip angle of 110°, the result is a compact, accurate, and low recoil pistol well suited to civilian and law enforcement users.
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