SMC 1" Stainless Steel J-Rack Tie-Off Bar 12301An extra large (1" diameter) "hyper bar" with extension and pin making locking off easier as well as providing additional friction when needed. Use this bar in place of a "regular" top bar and the resulting tie off is less likely to slip, yet it is easier to undo in order to resume your descent. The bar is hollow stainless steel to better dissipate heat and to stand up to the high wear associated with long descents or repeated use over an extended