As a final touch, ’56-3701F42′, the serial number of the destroyed weapon the metal is from, has been hand engraved beside the plate. It’s a subtle yet powerful reminder of just what this timepiece stands for. The Inversion Principle timepiece will be limited to just 20 pieces (10 in each metal) and will retail from US$350,000 with revenues from the sale of each timepiece used to fund the destruction of one thousand assault weapons in Africa.