Park Tool TNS-4 Star Nut Setter Tool The TNS-4 Star Nut Setter easily fits 1" and 1-1/8" forks. With a precision machined sleeve and a comfortable grip, the Threadless Nut Setter is used to install the star-fangled nut found on Ahead Set(R) and other threadless headset systems. Thread the nut onto the TNS, insert into the fork stack, and tap it in with a hammer. Sets the star-fangled nut to 15mm into the steer tube and keeps it straight for proper threading. Features Sets star nut a proper depth every time Durable steel driver with built-in sleeve Related Articles: Headset Service Star Fangled Nut Installation Manufacturer's Part No: TNS-4UPC: 763477008039 | Park Tool | Tns-4 Star Nut Setter Tns-4 Start Nut Setter For 1 Or 1-1/8