BRASS PLATE ( BP) A thin coating of brass over malleable iron or zinc die casting used to impart a yellow-orange finish to the casting and reduce oxidation of the base metal

NICKEL PLATE (NP) A thin coating of nickel which has been electroplated over malleable iron or zinc die casting to impart a fine , smooth, bluish-white finish to the casting.

STAINLESS STEEL (SS) high strength won't rust, needs no polishing and is is impervious to acids.

MALLEABLE IRON (MI) can be molded, pounded or pressed into shapes. Can be nickel plated, brass plated, or ZINC plated Tends to rust when the plating wears.

NAVY LIGHT ALLOY CARBINE (NV) Zinc, magnesium aluminum alloy chosen for mountaineering snap links, aircraft structures, with outstanding strength properties and extreme lightness.