51, 52, 53, 54, 55, 62
Ytb-code 51, 55, 62 = yellow layers
Ytb code 52, 53, 54 = black layer
Zinc alloy is a galvanic plated zinc alloy layer with iron. Zinc-alloy used preferably at the surface of the lock cases and hinges. The zinc-iron layer is after treated with a passivation to improve its corrosion protection.
Film thickness: 12 microns
Abrasion: Does not withstand heavy wear
Usage: Outdoor and indoor