The swivel clevis on this forged hook will engage with snap on Klein’s block & tackle #1802-30 and #H1802-30. Swivel prevents twisting and kinking of rope. Maximum load 750 lbs. THIS IS NOT AN OCCUPATIONAL PROTECTIVE DEVICE. DO NOT USE FOR HUMAN SUPPORT. Swivel opening: 1 3/16″. Throat opening: 1 7/8″. Overall length: 6 1/2″.