The PT-3 features a Two and Three Lens System which combines ballistic protection, and optical perfection, with a very versatile and adjustable frame design. Rubberized nose bridge adjusts to any size nose bridge and shape. T-Peg Elastic strap connects to the temples of the PT-3 and you can do any operation imaginable without having to worry about losing your eye pro. Wrap back design offers great side protection. Meets ANSI Z87.1-2003 High Velocity Safety and the military's Vo Ballistic Standard - MIL-PRF-31013.