These are bidirectional control valves made entirely of nickel-plated brass OT58 (brass), with NBR seals and a technopolymer control knob. They are suitable for regulating compressed air, water or mineral oil. For models 2810, 2820, 2819 and 2829 exists the possibility to connect plastic, brass or copper tubes, using nut Mod. 1303 and cushion sleeve Mod. 1310/ 1320.