Alloys: Most keychains are made of zinc alloy electroplated nickel, chrome plated, electroplated gold or other non-oxidizing non-ferrous metals. Normally, they will not fade. Gold should be kept away from the acid and alkali environment during use, otherwise it will easily cause fading.
Leather: Avoid sharp objects. If cortex protection oil can be applied properly.
About packaging: The default is packed in plastic bags or cardboard plastic bags. The cost of different packaging is slightly different.