For use with Heyco-Flex III Corrugated Tubing in trade sizes 3/8˝ through 1˝. Nontoxic and UV resistant. Rated for NEMA 4 and 4X applications when used with Heyco-Flex III Tubing. Rated for NEMA Type 3R applications. Easy, permanent assembly between the tubing and fittings: push the tubing over the fitting ferrule until the tubing "clicks" into place. Lightweight and lower installed cost. Quick and easy installation. Suitable for use in high vibration or flexing applications (automotive equipment, fiber optics, computer & peripherals, lab equipment, robotics, etc.). Resist salt water, weak acids, gasoline, alcohol, oil, grease, and common solvents. This feature is not assessed by UL certification or testing. For use in both wet and dry applications. If using a tapped hole, Teflon® tape is needed on the threads of the connector, for all other applications an O-ring and Locknut are needed to attain liquid tight. Use of an O-ring may be required for a complete liquid tight system with a non-threaded mounting hole. Locknuts included with Straight-thru fittings. Other locknuts available: Metal locknuts: NPT, PG, and Metric. Nylon locknuts: NPT, PG, and Metric. Patented.