I love Dinitrol stuff but their descriptions are rubbish.
Thanks to the nice lady at Rust.co.uk for explaining what I actually need for a crusty old Land Rover!
Their Dinitrol Aerosol Kit works out pretty good value.
No discussion of rustproofing would be complete without reference to one of the greatest threads of all time, Nige's waxoyled cat incident which will surely go down in internet history.