It's a brilliant idea, connect a prick punch and a center punch to each end of a powerful spring to produce the ultimate hammerless punch. Just place the working end on any surface, pull the striking end straight back and release. The recoil action of the spring produces a clean, sharp mark. The prick punch marks lightly, while the center punch creates deeper indentation for drill starts. The tips are hardened to 55 Rockwell, and the spring has a lifetime warranty. 1 lbs (0.5Kg) shipping weight.