is subjected to heat aging 120 u00b0 c u00d7 360 hours after the heat aging the heat resistance of each test piece is evaluated by bending one of the ends toward the other end over 180 degrees symbol o in table ii indicates that the test piece is not broken and therefore has an excellent heat resistance while symbol x indicates that the test piece is broken and therefore the heat resistance thereof is unsatisfactory each hose is cut to obtain a 500 mm long test piece one of the ends of each test piece is fitted on the outer circumferential surface of a nipple and the fitted end is externally tightened around the nipple at a 35 constant compression meanwhile the other end of each test piece is closed and a pressurized n 2 gas is blown into the test piece through the nipple the sealing characteristic of each test piece is evaluated by measuring a pressure of the n 2 gas when the n 2 gas begins in water to leak from between the hose 39 s fitted end and the nipple measurement is conducted two times before and after heat aging 120 u00b0 c u00d7 288 hours as emerges from the test results indicated in table i each of invention hoses no 1 and no 2 exhibits an excellent adhesive strength not only before the heat aging and but also after it thus the invention hoses are free from the problem of peeling at the interface between the.