These wyvale tanks leaked no matter what i tried i ptfted it had 3 new O rings sent out to me tried 3 new lids ptfted the thread on the actual tank and not 1 of those things worked,after a whole winter with 2 wet footwells i went for a custom made tank.If your going to go for 1 of these tanks go for a flat 1 cos i know of a few that have them and they don`t leak anywhere near as much if at all dur to the lids being recessed into the tank rather than above the tank.