Bulletproof glass. Technician examining a pane of Sentry-Glas Plus bulletproof glass hit by a bullet during testing. The force of the impact caused the lead bullet to evaporate and then recondense at the edge of the impact site. Despite this, the glass was not pierced. The pane consists of a layer of plastic sandwiched between two glass layers. The plastic makes the glass 100 times more rigid than previous types of bullet-proof glass. Such glass, which is used in military vehicles, armoured limousines, banks and museums, is also tested against blows from weapons like axes. Photographed in the Gun Testing Facility of the State of Baden-Wuttemberg in Ulm, Germany.