Home Depot has "Split Flex Tubing" for about $0.50 cents a Ft. I bought 30 Ft. of the stuff for $15. They have it in 3/8", 1/2", and 1", and is rated for -40 to 300 degrees Fahrenheit. When I bought the truck most of the electrical heat shielding had dry rotted away, and most of the wiring was lying bare on or in a hot engine compartment. My truck was having a problem where the "check engine" light would come on, and it would start running like it was in 'open loop'. I noticed that the only time the light would come on was when I hit a bump, or turned a corner a little quickly. I figured the problem was an exposed electrical wire getting grounded when it was banged around because all the electrical heat shielding was rotted away. Apparently I was correct, after driving the truck around for several hours, hitting bumps and turning corners quickly, the "check engine" light never came on, which it would normally have after that amount of driving time.