Captive nuts (T-nuts) with four prongs for inserting them into a wooden panel. These are useful for deck fittings where the underside of the deck is inaccessible once the deck is in place. They are also used for the bolts that hold our take-apart boats together.
These are galvanised (bright zinc plated, BZP) to help protect against rusting.
Please note that bolts are not included with these nuts.