Thx SGW, took it to the range this morning, wife really like it😂😂. I did as well. The person I bought it from is a long time competitive shooter. As for the thumb rest, I like it, though not really necessary on a 22. My P320X C has the gas pedal and for me helps control the muzzle. CheersFrom just looking at the picture you've provided, I'd say that the previous owner installed a few aftermarket parts. The VC trigger is obvious, so it's entirely possible that the VC "Performance Enhancement" kit may have been also installed. That so-called "gas-peddle" gizmo probably has more purpose in a 1953 Chevy, but if the original owner wanted to "look Tacti-Kool" at the shoots he attended, he probably needed that. Nice pick-up though, as other Mark IV uppers will interchange very easily. Watch Volquartsen's web-site to see as to when those become available in their "close-out" department, if that's of any interest to you.