They reduce noise, shaking, and enhance transportation safety. FOUR RECESSED D-RING CARGO TIEDOWN ANCHOR. 4 COMPLETE BLACK SETS OF D-RINGS: Includes 4 backing plates (4-7/8" x 4-1/2"), 4 recessed D-rings (3" x 3-1/4"), 16 carriage bolts, and 16 self-locking nuts.
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