Unlocked Crate TF2 is a box which offers you a random drop, including the chance of cosmetic items. The unlocked crates in Team Fortress Two are for people who want to try their luck and get different skins for their characters. There are ten unlocked crates in the game, nine for each class, and a final one - Multiclass (that is suitable for all classes).
You can buy or sell TF2 skins for the best prices on DMarket marketplace.