APR Head Bolt Kit. Fits Twin Cam 1999-2017, Evo Big Twin 1985-1999 & Sportster 1992-2021 AVO-AV921733 * Improved horsepower & torque

* Improved horsepower & torque

* Fits 2000up Models with 39mm Forks

* Length = 23-3/8"

* Twin Cam Style 4 Piston Caliper Upgrade

and then we made that one even better

APR Head Bolt Kit. Fits Twin Cam 1999-2017, Evo Big Twin 1985-1999 & Sportster 1992-2021 AVO-AV921733 * Improved horsepower & torquePRODUCT DETAILS : * The strongest bolts available! * Top engine builders demand quality fasteners! Secure your engine with complete confidence * Superior in strength and performance to any other cylinder stud head bolt kit on the market, this kit is designed to exceed the needs of high performance engines. * Dont Risk Head Gasket Failure! * Precision j form threads for optimum engagement, to prevent galling and promote more consistent torque loading.