U-Bolts most typically are used together with J-mounts or L-mounts, to bolt the J-mount or L-mount/bracket to a pole. They can be angled or smooth-curved for cylindrical and box pipe poles. U-Bolts are U-shaped, threaded bolts. They can be used to clamp antennas directly onto poles by tightening a grip around the pole. Various sizes are available for use on different pole diameters.