Heico-Lock Steel Washers are made of SAE J-403-AISI 1042/1045 or similar high carbon steel.
Heico-Lock Wedge Lock Washers are perfectly suited to work with structural grade and high tensile bolts and nuts (8.8, 10.9, 12.9., ASTM 574). Large O.D. locking washers are recommended for use on large/long holes (e.g., with flange nuts or screws), painted surfaces or soft materials, (e.g., aluminum).