TIGHTLOK W Steel Mat, also known as W Steel Mat, W Steel Strap, is widely used for mine and tunnel roof support, usually combined together with wire mesh and bolts to form a whole support area.a n Our branded Tightlok Roof Mat can match the quality of international standard, and have characteristics as: 1. Raw material is high strength alloyed steel 2. with very good strength and rigidity 3. excellent anti-bending property