Accessory slots and combinations
Accessories generally need functional slots to grant effects, cannot be duplicated in equipped slots, and can be combined at the Tinkerer's Workshop.
How it works
The accessories page says accessories provide stat boosts or special abilities and generally must be placed in accessory slots to work; informational accessories are an exception. Duplicate accessories cannot be equipped. The Tinkerer's Workshop can combine different accessories into a new one that combines component effects and often enhances or adds effects. Vanity slots provide no stat bonuses.
Read the supporting references
A source-bounded reference to selected Terraria weapons, armor, accessories, and modifiers. It records effects and restrictions stated in the retrieved passages. Comparative strength, optimal builds, complete coverage, and current patch status are not verified. Guidance explains the referenced mechanics; it is not a tested damage ranking. Check the stated edition and source version before applying a patch-specific detail.