What cars are you using? Honestly my first Century was the Marathoner and I'm disappointed with it and will never buy it again. It lasted over 2 years for my car with countless jump starts within that duration coz I didn't use the car for 5-7 days. Now I'm trying the Century Ultramax which is supposed to be their best model and it is better but not by much. It also already need to be jump started a few times, not yet 1.5 yrs though.

I also often hear recommendations for Amaron but never hear that they can last 7 years! Maybe next change I will try this brand but I will not try Century anymore, not even their Ultramax.

Now I am really curious, what small screw is it that you use and how was it use ?