This set contains a wooden block and four screws that thread into permanently fixed, threaded receptacles. The board also has two insets: one for holding the Allen key and one for holding the screws once they've been removed.
This set lets students practice the action of using an Allen key (i.e. hex key) by removing and re-inserting four internal hex screws using the supplied key.
Note: Take care not to over-tighten the screws as this may result in the threaded receptacles being removed from the block when unscrewing.