These mushroom-head bolts are available with M6, M8 or 1/4-20 threads. All are steel, either plain zinc plated or black zinc plated, and available in a large range of sizes from 12mm to 70mm (length is the bolt barrel only – head height is 3mm). The broad (15mm to 17mm) heads distribute force over a large area, making these bolts ideal for use with both hard and soft woods, in addition to surface-mounted hardware. Made in Germany.