Waxoyl Buddy..
Youve got your Waxoyl Shutz, which is Full on Underbody seal, but its very difficult to work with once its on, Goes incredibly hard, youl have to chisel it off to do anything..
Or theres good old normal Waxoyl which will give ya good protection if ya do it each year!.. it creeps into lil gaps and also is self repairing if it gets chipped off..
You can but both kits to put it on if ya wanna do it yourself.. Waxoyl High pressure sprayer for normal waxoyl.. bout £25 for sprayer, and a good 5Litre of Waxoyl £40 or you could just go to a garage and get them to do it for about £120
The Shutz is abit harder to put on, unless you have a Shutz gun, or you can paint it on, but ya wont get it everywhere that way...