Mastercool is the leading manufacturer of professional quality AC/R manifold gauge sets. Their manifold gauge sets are constructed of the finest materials and machined with precision to the highest standards. At Mastercool, every manifold they build is built to last. With features like: 3/8” BORE 4-WAY BALL VALVE MANIFOLD, Full 3/8” bore through the block for increased flow resulting in considerably faster charging and recovery, Ball valve rotates 90˚ between two Teflon washers requiring little effort to turn, even under pressure, Opens and closes quickly with only a quarter turn, Knob position shows whether valves are open or closed (Vertical = OPEN, Horizontal = CLOSED). Includes set of four 96" hoses. Couplers are NOT included with this set.