Product Description: Condition: Aftermarket 100% Brand New They are for the head bolts on either side of the spark plugs. Outside Diameter :28mm (1 1/8″) Inside Diameter : 15mm (9/16″) Material: High Quality Aluminum Color: Black Fitment: Fit Harley-Davidson all Twin Cam models 1999-Later, all Big Twin 1340 Evo Models 1985-1999, and all Sportster models 1986-Later . Package included: 4x Head Bolt/Nut Covers Note : Please check the Size before you purchase !