From my 18' TROPIC GTI catamaran (sold) width 2,5m,

there remains this emergency trampoline, braided mesh,

lets water and air pass through, very little used,

always stored under cover.

Fasteners to be foreseen : on the front by a rope in the front beam, on the sides by eyelets and lacing, on the back by lacing on riveted bridges on the rear beam