Yep, that's the entirety of the circuit. This will work with any drum brain I know about (but it's been a few years since I did it, so YMMV...) This worked with an old Alesis D4 that I bought at a pawn shop. And I know it'll work with a DM5, etc etc.
You can play with materials a little for the surface -- I used plywood and mousepads. Mousepads are a little soft (the traditional 3/8" thick foam rubber with a cloth backing type...), Different thicknesses of plywood affect sensitivity, etc. If there isn't enough mass, false/double triggering happens.
It's a fun thing to try, and the materials are really cheap (and there are DIY drum trigger boards you can find on the internet now...)