Made in USA. Install this Aluminum #10 Male O-Ring x 3/8" NPT Male Adapter Fitting in your intake manifold and/or water pump so that you can use #10 beadlock crimped fittings instead of conventional heater hose barbs. Use 358130, 358230, 358330 or 358430 with reduced barrier hose. Use 354100,354200 or 354300 with 5/8" heater hose. We prefer to use #10 Reduced Barrier A/C hose for heater lines as conventional 5/8" heater hose can't be bent in a very tight radius before it starts to kink.