Cotter Pins are made of low carbon steel with rust-proof zinc plating. Contains The 6 Most Popular Sizes: 1/8″ x 2″ 57pcs, 5/32″ x 2-1/2″ 30pcs, 3/16″ x 3 ” 20pcs, 1/4″ x 2″ 25pcs, 1/4″ x 3″ 10pcs, 5/16″ x 2-1/2″ 8pcs – Convenient Re-sealable plastic organizer case.