Pryor PPDS10030 09 Dot Face Lowstress Punches, 10 Piece, 1/8", 3.0mm

I picked these up from a recommendation by my machinist friend as they are the ones he himself uses. They arrived timely and my goal was to use these numbers on my old cars valves since I’m not putting them in place any time soon. Yet they have been hand lapped to each seat & thus must stay with those seats when finally installed.I used my baby Thor hammer (3lb) and was gentle with it, practicing on the old valve face 1st. To practice I drilled a hole in a block of wood & slipped the valve in the hole to hold it in place. Once practiced up, I inserted each valve in its mated seat to stamp each valve. I tried to get the stamp closer to the center of the valves top to distribute the hit better. The hardest part was trying to hold the stamp perfectly flat to get the proper & full stamp. Yes, there were some I didn’t get right on the 1st hit. However I found it pretty easy to put it back in place lining up existing dots to stamp again & it worked.Overall I really like these stamps & they work well. It takes a little practice & patience to do it right but then doesn’t anything of valve too!10/26/19 Update: worked well on my old straight 8 engine before disassembled, marked piston tops & valves.