You push the compartment with the screwdriver & bits into the sleeve until it clicks into place. When you depress the top of the case several millimeters, it is released again. Similar to the way that a memory card is inserted into / released from a card slot. In a toolbox, it would probably be best to have the case upright in its own holder, so that no other tools can accidentally put pressure on the top and release the content. The screwdriver and bits themselves are held in place pretty securely.
