I installed the stock on a Mossberg 940 Pro Tactical SPX (#85162). There are a couple of design changes on this 940 which affect the installation, but they were very minor. The first is the return spring retainer. It has been redesigned so that the return spring tube tool (supplied by Mesa Tactical) will not insert correctly. This is not really an issue, as the return spring retainer sits high enough to be depressed with your finger so that the retainer pin can be removed. The second is the roll pin which sits to the rear of the receiver and lines up with a groove on the stock itself. Due to its length, it will not allow the Urbino to sit flush with the receiver. It cannot be tapped deeper into the receiver. Ultimately I removed it with vice grips to allow proper seating of the Urbino. All other installation steps were followed according to the Urbino manual. The fit & finish on this stock are FANTASTIC. The length of pull is excellent. The shotgun sights-in, handles easier and is better-balanced with a pistol grip stock. The design has none of the after-market look of other offerings - if I didn't know better, I would believe it was a factory stock. In my opinion it is a vast improvement over the factory buttstock, and I highly recommend the upgrade! (One issue, I did not receive a sling loop with the stock. I am sure this can be easily corrected by Mesa Tactical) Five Stars!