Credit: Screwpop
Uses a standard two or four notch utility blade, available at any hardware store.
http://the-gadgeteer.com/2015/03/13/screwpop-utility-knife-is-a-box-cutter-you-can-carry-on-your-keychain/
http://www.screwpoptool.com/utility-knife.html / Screwpop Utility Knife slimmest most compact design packing Utility Knife fits standard utility blade 2 or 4 notched notch four controlled depths of cuts ingenious lever system blade stop tension locks mechanical friction-fit engineering blade adjustment moving move lever thumb-nail thumb nail thumbnail users Utility Knife various cutting needs attaches keyrings carabiner clips fits small pocket TSA blade any hardware store /
