Picks up an item from or puts an item into an equipment slot. If the cursor is empty and the referenced inventory slot contains an item, that item is put onto the cursor. If the cursor contains an item (which can be equipped in the slot) and the slot is empty, the item is placed into the slot. If both the cursor and the slot contain items, the contents of the cursor and the inventory slot are exchanged.

An item picked up from an inventory slot is not removed from the slot (until put elsewhere); when an item is picked up, the slot becomes locked, preventing other changes to its contents until the disposition (movement, trade, destruction, etc) of the picked-up item is resolved.