As used on the Murrays No-Cut Hi-Low Trapeze Adjustment Kit. Precision molded Acetal sheaves run on stainless steel or Torlon® ball bearings to provide high performance and low friction.
The Ronstan back-to-back blocks have 3/4" sheaves and 1/4" maximum line diameter. Maximum working load is 550 lbs.; breaking load is 1210 lb. Weighs only 1.1 oz. Ronstan part #RF20284.