strange tubing eh, large reducing to small. My resoultion was to buy standard black hose at auto parts, of the smaller diameter. Then went to lowes, got a pvc coupler, I believe, + a reducer. just press fit together. It fit perfectly in the defroster tubes. use nylon zip ties to attach hose. If you look through windshield you can see the white, so just paint the pvc flat black. I`ts been working well for me for years.Anyone know if there is reproduction under dash heater tubing available? I have not seen any advertised.
Thanks