Number one and number two steel are types of heavy metal scrap (HMS). Both consist of clean iron and steel having a maximum size of 60"x24". The only difference I have been able to find is in the minimum thickness which is 1/4" for No. 1 and 1/8" for No. 2.
Specifying length can also limit the sizes of HMS 1 and HMS 2. For example, HMS1 (1 foot) limits the maximum size to 12"x12".
Specifying length can also limit the sizes of HMS 1 and HMS 2. For example, HMS1 (1 foot) limits the maximum size to 12"x12".