Probably the best $15 Ive spent on any HK accessory. Sits super low and very tight to the receiver. Screws have small tension springs to keep it tight- no need for locktight. Well made and the materials are of very good quality for the price. No mods required to fit a PTR91. Has some the largest screws I've seen on an HK mount allowing a lot of torque to be applied. Better than 2 other inexpensive HK mounts I've tried.
Pros: Clamps down like a pitbul. Cheap!
Cons: None
This review was written in the old system and had content requirements that are different than reviews written today.