No.55 R/44 1.8" Zs56 / Zs66 Headset

For tapered 62mm / 72mm OD head tube, to suit 1-1/8" to 1.8" tapered fork. SPECIFICATIONS

HEADSET TYPE: Zero Stack Upper/Zero Stack Lower Cup
STEERER TUBE: Tapered 11/8" to 1.8"
MATERIAL: Alloy
STACK HEIGHT: 11.2mm (8.8mm 2.4mm)
UPPER CUP: 56mm Flush Cup
LOWER CUP: 66mm Flush Cup
UPPER BEARING: 36° x 45° 11/8" ACB Sealed Bearing 51.8mm OD
LOWER BEARING: 36° x 45° 1.5" ACB Sealed Bearing 61.9mm OD
WEIGHT: 139.1 grams