Black poly mesh stainless steel. When properly framed it is an excellent light security window and door screen (resists cans,bottles,rocks,BB's,and casual forced entry). This is one of the mesh specifications that is approved by (Department of Housing and Urban Development). It cuts with very sturdy hand or machine shears. Rohs compliant. This sturdy market grade mesh is woven from a standard wire diameter which is heavier than the wire used to weave bolting cloth. Meets ASTM E2016-11 and UNS S30400.