Pads & Leashes
The leash line must be tear-resistant yet flexible so that nothing separates the surfer from his surfboard. From the thin competition leash (5.5mm only suitable for light boards and smaller waves), through regular leashes (7mm all-round leashes for all board types and conditions) to big wave leashes (extra thick 9mm leashes for SUP boards or extreme conditions; these leashes are very stiff and therefore not recommended as all-rounders for surfboards).
The length of the leash line depends on the length of the board. The rule of thumb here is: The leash should be specified a maximum of 6 inches longer or shorter than the board is long:
6 foot leash = 5.6 - 6.6 foot board length
7 foot leash = 6.6 - 7.6 foot board length
8 foot leash = 7.6 - 8.6 foot board length
9 foot leash = 8.6 - 9.6 foot board length
10 foot leash = 9.6 - 10.6 foot board length