Check the listing for details. Wolf Tooth Knock Block Headset Spacer 10mm Trek Knock Block Compatible Silver. Condition: New. Listed at 11.99 USD. Wolf Tooth Knock Block Headset Spacer 10mm Trek Knock Block Compatible Silver Wolf Tooth Knock Block Headset Spacer 10mm SilverBecause details matter when tricking out your bike, match all of your colors! Wolf Tooth headset spacers are precision machined in Minneapolis and are ready to bling out your Knock Block equipped Trek.Knock Block compatible headset spacers offered in an array of colorsNot for use with standard headset system Has the patented protruding tabs on topside and recesses on bottom sideCompatible with 1-1/8" (28.6mm) straight or tapered steerer tubes7075 aluminumMade in USA810006802665 Powered by Solid Commerce The All-in-One Listing, Inventory & Order Management Solution for Online MerchantseBay integration by