Ideally you want the spreader bar to spread the load to the back of your harness, and not move up and down. On top of that there are some details that can help you get the most out of your time on the water.
Do you want to rotate, or do you trim your sail by sliding on the harness hook ?
About spreader bars
Lengths:
Standard length 10” / 25 cm., but they also exists in 6”/ 15 cm. and in 12” / 30 cm. length.
Marterieal:
stainless steel, aluminium and carbon
Special options:
roller hook, quick release and sliding hook
Ends:
there are many different choices of end pieces, which often accommodate different manufacturers harness models.
Sliding hook / rotate stance
If you want to have a sliding bar, so the best solution is a bar with a single "hole" at each end. Check whether it fits the strap on the harness.
A bar of only 6 "gives you maximum rotation, but a bar on 10" work well, particularly for medium and larger sailors.
Upside down
There are some windsurfers who like to have their spreader bar upside down. This changes the way you get in the lines, and how you stance will bee.
Roller hook
If you prefer to have ”great” distance between your trapez lines, and you sheet your sail in and out by sliding the harness linen on harness hook. Then you perhaps could consider whether you should have a spreader bar, with a roller.
YOU CAN SEE MORE ON SPREADER BARS FORM DAKINE HERE
