Durable M7.5 T30 countersunk masonry screws used to directly fix window frames to the masonry, concrete and lightweight block. Available in both YZP and bright zinc plated. Lengths range from 80mm to 180mm – all boxed in 100’s. A pilot drill of 6mm or 6.5mm diameter is required. To complement the masonry screws why not use the Torx30 x 25mm driver bits?