Stainless Fiddle Block 10-4510 Series Fiddle Block with Stainless Steel cheeks. Works with 10 55 for a 4: 1 purchase. Delrin(tm) sheaves run on Nomex(tm) Teflon(tm) bearings for low friction and high safe working loads. Unique design features a single top sheave and two in line sheaves to spread the load reducing friction and chafe. Stainless Steel D shackle run on a swivel head that may be locked in plate to avoid line twist. Bolted construction allows for easy maintainence.