1/8" 1/4" 3/8" PT Male x 6/8/10/12mm OD PU Tube Air Pneumatic Quick Coupler Fast Twist Hose Stainless 304 Connectors Fitting: Shop our selection of high-quality PT Male x OD PU Tube Air Pneumatic Quick Coupler Fast Twist Hose Stainless 304 Connectors Fittings. We offer sizes ranging from 1/8" to 3/8" and various tube OD options. Perfect for any pneumatic application!