Features and Benefits: . Anti-flutter gauges smooth out needle movement. Yellow hose includes shut-off valve. Piston type free-floating valves reduce o-ring wear. Extra access port for vacuum line. Gauges can be recalibrated to maintain accuracyR-134A Brass Manifold with 3 60" nylon barrier hoses and standard R-134A Couplers. Coupler sizes 14mm, 15mm, 16mm, 17mm, 18mm and 19mm. Inner nylon layer hoses meet EPA, SAE and UL standards.