We had great seller customer service. When installing these, DO NOT pop off the retaining clips. Merely loosen then with the screwdriver until the strut pops on the knob and pull out the screwdriver. I popped one of my clips off and it bent the clip so it wouldn't work. I told the seller about it, and they sent me a brand new replacement. Awesome. I used these for a Leer 700 tonneau hard cover for my truck. I sorta wish I would have gotten the 150 lb version instead of the 100 lb version because it doesn't initially full extend, but that is my fault and they are still function in opening and propping up the cover up about 80% of full extension.