This SMC KQ2H straight reducing union is a PBT tube fitting for connecting two tubes of different sizes. It has push-to-connect metric tube connections on both ends. The body is made of polybutylene terephthalate (PBT) for resistance to corrosion, and the tube seals are made of nitrile butadiene rubber (NBR) for resistance to oils and extreme temperatures. A chuck and collet provide secure retention of tubing, and the release button allows tube removal with little force. The fitting can be used with nylon, soft nylon, polyurethane, fluorinated ethylene propylene (FEP), and perfluoroalkoxy (PFA) tubing. It has an operating pressure range of -14.5 to 145 pounds per square inch (psi) (-100 kPa to 1 MPa), an ambient temperature range of 23 to 140 degrees F (-5 to 60 degrees C), and a fluid temperature range of 32 to 104 degrees F (0 to 40 degrees C). This PBT tube fitting is Restriction of Hazardous Substances (RoHS) compliant, and can be used in a broad range of fluid power applications, including temperature control, compressed air equipment, medical instrumentation, and motor vehicle controls, among others. Specifications Compatible tubing materials Nylon, soft nylon, polyurethane, FEP, PFA Fluid Air or water Operating pressure range 14.5 to 145 psi (-100 kPa to 1 MPa) Operating temperature range (ambient) 23 to 140 degrees F (-5 to 60 degrees C) Operating temperature range (fluid)) 32 to 104 degrees F (0 to 40 degrees C) Tube fittings are components used for connecting, branching, terminating, and changing the direction of tubing in pneumatic and hydraulic systems. They are made of brass, stainless steel, polybutylene terephthalate (PBT), and other materials that resist corrosion and wear. Tube fittings have various types of connections, including threaded, welded, barbed, and push-to-connect (also called one-touch). Push-to-connect connections do not require tools or sealants. Tube fittings are used in various applications, including machine tools, airplane and truck controls, and automated production lines, among others. SMC Corporation manufactures actuators, valves, airline equipment, connector fittings, electrical products, vacuum products, dryers, temperature control chillers, and accessories. SMC Corporation of America is headquartered in Noblesville, IN, and meets International Organization for Standardization (ISO) standard 9001:2008.