[Chucks' Size]The closed air chuck has 1/4inch FNPT air inlet,ball air chuck function is to enable the shutoff valve to shut down the air when the stem is not opened. The Closed Tire Chuck also has 1/4inch Female NPT THREADS fit most air inflators. The Dual Head Air Chuck has 1/4inch FNPT air inlet,the maximum air pressure is 150 pounds per square inch.All the thread is 1/4inch Female NPT,suit for any 1/4inch Male NPT fittings. [Material]All the products are made of Solid Brass construction. Compared with stainless steel and plastic, it is more - and , and can meet the needs of air pumping and air pressure measurement in various scenarios. [Adapters' Size]1/4inch Coupling x 1/4inch Male NPT Threaded Full Quick Connect which can be used with the 1/4inch Female NPT air chuck., Weight: 0.4078551847 Pounds, Manufacturer: puhae