This swing hanger is 3 1/2” O.D. with an 11” circumference. It has a .51 ID oil light bearing and axle bolt with lock tight nut and accepts a 12mm bolt. The stamped steel has more ability to bend so they will not snap when torqued too tightly. The lower half of the swing hanger body has a figure eight pendulum with a sintered bronze bearing incorporated into it, to reduce wear. The bronze is impregnated with oil so the bearings do not have to be oiled. The pendulum is 1” wide and is a completely closed figure eight so that the connecting S-hook or shackle cannot be dislodged from the hanger. The two halves of the hanger are bolted together with a 12mm carriage bolt with a hex lock tight nut. The pendulum is held to the hanger with a #12 axle bolt with a long shoulder so the bearing does not ride on the threads. It also has a lock tight nut. Do not torque more than 25ft-lbs. when installing.