Blew rear brake lines!!!!

One of the rear brake line blew on me this AM. I have a 97 4X2 V6 with Auto does anyone have an idae of what size line these are. I suppose I am going to have to do both rear wheels and the main one running back. Thanks in advance.

I would remove the defective brake line and take it with me and buy a new piece at the parts store. Its very important to matck the thread size. Original equipment has a steel spring wound around it for protection against damage.
This is along the back axle for protection. I have bought a good section at a scrap yard for these. A lot depends if you use the truck for running in the woods. You can ask the dealer parts whats is available.