Super Mica is used to open locked doors by sliding this material in a door jamb and forcing the spring latch bolt into the door lock. This material is tough enough to wedge into most door jambs several times. This method is similar to the old credit card in the door jamb method except that this material is thinner and more flexible than a credit card.
This pack of 6 pieces of plastic will open virtually any spring latchbolt. These will not work on deadbolts or deadlatches. Each piece lasts longer and performs better than anything you've ever seen before. Better than shim steel. 2 thicknesses per package (3 of .020", 3 of .015"). Includes a nice carrying case.