These are Longer 85mm (MAX) or 65mm (Slim) Mast Plate Bolts for attaching your Gen2 Foil Drive to you board that features deeper foil tracks, base plate shims or for use with the Foil Drive External Antenna.

Please measure your required length to ensure you are using the correct bolts that engage with the t-nuts securely to avoid damage to your board, Foil Drive or foil mast.