For the Twist Top frame, taking out the included insert to reduce it to fit a smaller tube, it was too big by a small margin. This meant I wouldn't be able to clamp it down hard in place, but that might also mar the finish. I needed something that was just thick enough to take up the space and help keep the clamp stay put such as a thin rubber material. I remember I had some left over rubber matting for lining the drawers of my tool chests, this turned out to work perfectly. I used double sided tape to adhere the matting to the inside of the clamp pieces and trimmed to fit.
PIAA 1.5" or 1.75" Adjustable Roll Cage Bar Light Mounting Aluminum Clamps
