DBI/SALA,Glyder 2110808 Sliding Beam Anchor, Fits 3 1/2 To 12-Inch Wide I-Beams, Up To 1 1/4-Inch Thick, Silver Provides complete horizontal mobility, tie-off overhead or at your-Feet (use with Force2 shock absor Anchor effortlessly slides across the beam on its wear pads, eliminating metal-to-metal contact Unique guarded locking mechanism protects the anchor from accidental disengagement Dual beam grip adjustment prevents twisting and turning as it moves along the beam