Machined out of one solid piece of 17-4 stainless. In most applications if your pin size matches....all you have to do is slide your old slide stop out, slide this one in, and you have a thumbrest on your Limited or Open USPSA gun. No drilling, no tapping, no awkward installations. These are top quality parts, Top shooter Lesgar Murdock Jr.has been running the first prototype since the beginning of 2013. He has been winning top level matches with this part and swears by it.
These Nitro Fins retail for $120, which is less than the cost of a top quality slide stop, thumb rest, drill, tap and installation.
PLEASE READ: Check your current slide lock for pin size. Use caution test fitting it before test firing at the range. The Nitro Fin by design fits close inside the slide lock relief of the frame, some gun smith work may be required.
The Pin size is 0.199
Slide lock does lock the slide back manually, but does not automatically on the last round. (Top Level Gunsmith Feature)
I recommend you drill your own detent due to some firearm manufacturers not having the plunger pin in the same locations. (EX: Older Para and Caspian setups). Creating this detent will lock down the slide lock from ever being engaged on accident, but I have no report of this happening... it's just good insurance.