Well it was a brand new rubber gasket that came with it, now its been on and off 3 times. The first time I know I overtightened it, the second time I think there was a chunk of plastic caught between the gasket and tank that peeled back when I tried to take the tank out of my slightly jacked up frame, the third time will be tomorrow morning. The base and tank are smooth and dry, if it leakes ill take a pic after I throw it across my garage