ground access mats 1/2 Inch 60 tons load capacity nz 15mm thick brown Ground protection mats 60 tons load capacity To calculate the tons needed for other metals just multiply number times the tons required for punching mild steel: Aluminum (2024-0): multiply x .36 Brass (1/4 hard): multiply x .70 pper (1/2 hard): multiply x .52 High Carbon Steel: multiply x 1.60 A36 Steel (recycled): multiply x 1