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Trek Knock Block 58-degree Headset Assembly

Model W543168

Service and replacement parts specifically for Trek Knock Block Technology.

Product details

Compatible with all Trek Knock Block models
Includes crown race, bearings, top cover, frame chip & fastener
Must be paired with Knock Block stem and Knock Block spacers
Knock Block headset spacers not included

Manufacturer part #	IS-2-HBS/42/ACB
Steerer outer diameter	28.6mm (1-1/8") / 38.1mm (1-1/2")
Crown race inner diameter	39.8mm
Cup Insertion OD	Integrated
Stack height	8.7mm
Bearing type	Sealed
Headset type upper	Unthreaded fully integrated
Headset type lower	Fully integrated
Material	Aluminum

We reserve the right to make changes to the product information contained on this site at any time without notice, including with respect to equipment, specifications, models, colors, materials, and pricing. Due to supply chain issues, compatible parts may be substituted at any time without notice. Prices shown are manufacturer's suggested retail prices.

Weights are based off pre-production products at time of publication. Weights may vary in final production.