Different Diameter Straight Coupling - KQG2 Series SMC’s KQG2 stainless steel range provides engineers with a choice of high performance, lightweight, compact push in fittings for when resistance to corrosion, chemicals and high temperatures is vital. 30% smaller and 62% lighter than the existing KQG range and available to tubing diameters from 3.2 to 16mm. Suitable for use with compressed air, water, steam and able to perform across a diverse range of pressure (-100kPa to 1MPa) and temperature conditions (-5°C to +150°C).