The Robinair 42216 4-Valve Aluminum Manifold is constructed from solid aluminum for added durability needed for repeated, tough daily use. The contoured, easy-to-grip hand wheels are color-coded for quick and easy identification. Full 3/8" bores throughout the body aid in getting the job done quickly and efficiently. The large and easy-to-read 3-1/8" (80mm) gauges are protected by Lexan lenses. A 3/8" vacuum port is featured for use with larger hoses to cut down on evacuation time. The improved face seal valves allow for easier operation. The better design provides a tighter seal which means less wear and improved flow. The proven, double O-ring piston design allows for extra reliability and a longer service life.