Info from Manufacturer: Info from Manufacturer: For adjusting banjo head tension. Our traditional nickel-plated steel bracket hooks are used with bracket hex nuts to adjust the tightness of a banjo head. #0088 has a round cross-section and fits a notched tension hoop. #0096 is flattened at the top to fit a grooved tension hoop. Our bracket hooks are 2-1/2" (63.50mm) long. The 8-26 threaded portion is 1" (25.40mm) long. Round hooks are.158" (4.01mm) diameter; flat hooks are .138" (3.51mm) diameter.