Very good, could be better. - Mesa Tactical LEO Gen II Tele Collapsible Shotgun Stock Adapter

This does that it's supposed to. It allows for a carbine style buffer and standard ar grip to be attached to the back of your mossberg. Lockup is good. Instructions could be a bit more helpful. I didn't realize this is Only for carbine stocks, as there is no provision for a stock that requires an indexing dimple. It says this in the manual but not in any ad. But I'm sure that's what most people want. I am using an a1 stock, and was able to get it to work with a modified I cut with a Dremel. Note that this mounts your stock at the same height as your original stock, which may be low for some optics. I believe they also sell one that mounts it higher. Or, like me, you can just get a cheek riser.