Mishimoto MMHOSE-GM-17U GM C/K Truck (305ci/350ci) Silicone Upper Radiator Hose, 1978-1986, Black Direct fit for the 19781986 GMC C/K Truck with a 305 5.0L or 350 5.7L INNER DIAMETER: 1.18-1.54" OUTER DIAMETER: 1.57-1.93" Maximum Temperature: 330F Constructed with high grade silicone and heat-resistant embedded fibers Mishimoto Lifetime Warranty