0.350 - 0.625 Inch Grip 1/4 Inch Dia x 0.81 Inch 5052 Aluminum Standard Flange Dome Head Blind RivetThe RivetKing In Lock is a structural rivet with an internal locking feature. the locking feature is not visible when the rivet is applied. the mandrel is retained within the shear plane yielding high strength under shear loads and the internal lock insures positive mandrel retention which results in high strength under pullout loads. Typically used in the manufacturing or repair of truck bodies the In Lock is leak resistant and has excellent clamp up