Another first from Rock Thompson are these quick-to-attach, high-strength, swiveling rope blocks. Like Rock Exotica's popular swivel connector, these blocks eliminate twisting from rope rigging systems with smooth, ball-bearing action. Each precision-fabricated alloy block has a unique button-activated release feature that allows instant access to the sheave for midline attachment. Double Locking Feature. The milled alloy attachment eye is large enough to accept most carabiners and snaps. Rope capacity up to 1/2", 1,350 lbs working load limit.