- Steel cups - Steel retainer bearings - Available in chrome or black - Steerer Dia: 25.4mm - Cup Dia: 30mm

Service and replacement parts specifically for Trek Knock Block technology. Genuine replacement parts Get your bike back on the trail with the headset parts you need. - Trek proprietary headset components compatible with Trek Knock Block models - 72-degree headset fits 2021 Slash 29 - Includes crown race, bearings, top cover, frame chip & fastener - Frame chip has display tabs to connect Bosch Kiox Mount sold separately - Must be paired with Knock Block stem and Knock Block spacers - Knock Block headset spacers not included