I'll have to pass unfortunately due to the rail missing. (I really like it though lol.. just cleaned up an original version so fun to tinker with). BTW.. the HP version of the one you have I believe can adjust from 400 to 1100+ psi. 7500psi burst disk might indicate it's a 4500psi version.Just stripped cleaned and lubed it and it all looks fine. Obviously it's got the built in dovetail but I haven't got a rail with it. It's got a 7500 burst disk in it so I'm guessing its HP. Let me know if you want it