A raised central bar of each sliderbolt 417 allows enough space between the bindings base plate 421 and the rail 411 .
The binding base plate 421 can freely move the length of the rail 411 .
A raised central bar of each sliderbolt 417 allows enough space between the bindings base plate 421 and the rail 411 so that the binding base plate 421 can freely move the length of the rail 411 .