Safety glasses esp. for igniting fireworks - from three pieces of synthetic transparent sheet slotted into each other

摘要

Three components stamped from a sheet of "LEXAN" (RTM) or other transparent synthetic material having light absorbent characteristics, comprising two arms and a frontal piece, form safety glasses. They also have application as sunglasses. Each component has a series of slots allowing the frontal piece to be engaged with the side pieces, to give different breadths of vision and different arm lengths. The glasses are cheap to produce and comfortable to wear, so that they can be distributed widely.