Plug KQ2 Series KQ2 Series Plug tube from SMC. Suitable for use on positive pressure and vacuum, available in various sizes. Tube-to-Tube Fittings & Plugs Sealant coated threads minimise assembly time. The fittings can be used on vacuum or positive pressure lines. Suitable for use with nylon, soft nylon or polyurethane tube for compressed air or water (general industry) conveyance. Maximum operating pressure 10 bar Maximum vacuum operating pressure -100kPa Proof pressure 3MPa Ambient and fluid temperature -5 to +60°C (water 0 - 40°C)