Nothing longer than 1=inch, beware plumbing and realize you are asking a lot of 1/8" paneling or plywood? Maybe better to GLUE up a board using CLEAR LEXEL, or construction adhesive, then screw to that? Good Luck
Thanks I do appreciate you taking the time to answer. after looking at it again I am going to go with glued on backing first. also I only for towels linen so there won't be any real weight on it.