This headset suits bikes with 56mm ID headtubes

HEADSET TYPE: Threadless Zero Stack Cup
STEERER TUBE: 1 1/8″ to 1.5″ tapered, or 1 1/8″ straight steerer with a reducer crown race
MATERIAL: Alloy
STACK HEIGHT: 13mm
UPPER CUP: 56mm Flush Cup
LOWER CUP: 56mm Flush Cup
UPPER BEARING: 36 x 45 1.5″ ACB Sealed Bearing 51.8mm OD
LOWER BEARING: 36 x 45 1.5″ ACB Sealed Bearing 51.8mm OD

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