The FSA Hammer Heavy duty headset features heavy duty retainer bearings. 12mm deep cup design for strength and stability. Nylon top cover & plastic seal allows for a reasonable price point and eliminates grime and debris. The FSA Hammer headset is constructed of lightweight forged aluminum. Upper diameter 5/32'' x 20 retainer bearings,Lower oversized diameter 3/16'' x 20B retainer bearings.
Stack Height: (12.8mm/11.9mm=24.7mm)
Steerer Diameter: 1-1/8''
MFG. Part #: 141-2340