The UrbanArtt Civic SCS Clamp comes with a shim to fit standard and oversized bars. It also uses M8 clamp bolts which will help keep the clamp tight. The cutouts in the clamp were designed to remove weight, but keep metal in the spots that matter for its structural integrity. The Civic SCS comes in at 6.53 oz thanks to the cutouts, and is a great option for any setup! Clamp does NOT come with a compression washer.