Galvanized steel wood beam hanger uses only one bolt with teeth on top of the hanger to prevent it from turning after installation. It has a .51 ID oil light bearing and axle bolt with lock tight nut and accepts a 12 mm bolt. Use on a wooden swing frame. It has a shackle pendulum, opening 1/2" wide, that does not require an S-hook for connections to the chain but is tamper resistant and requires an Allen wrench with special hole to open and close. Plate is 2 ¼" x 1 ¼". This product should last 2 years in harsh conditions and up to 5 years in optimal conditions. Some conditions may require replacement sooner.Tensile strength is 510600 lbs. Sold as set of 2.