This is just my recent experience with the Nitelighter NL-55 that is an L shaped bracket that goes over the side (to act as a temporary replacement for a non functioning built in light until the next time the vinyl liner needs to be changed in a couple of years. I bought it online during a memorial day sale, the light came in, I installed it last weekend and it does not work. The seller's policy is not to take returns on defective merchandise instead they referred me to the company that makes it, I go their web page and see the usual Mon-Fri customer service hours, and an online form to fill out to request an RMA#. I fill out the form, get the auto reply saying a customer service rep will be in touch, that was Sunday, this in now Tuesday afternoon, so far no word from them.
Ike
P.S. their web site says allow 6-8 weeks for warranty work