18 Pieces Quick Coupler Set Air Fittings Connector Kit Including: 1/4 internal thread female connector,1/4 external thread male connection ,1/4 internal thread male connection ,1/4 double male connector Application: Air piping and Pneumatic tool, Automotive , Air compressor, Mechanical Engineering High replacement couplers provide secure and quick fittings, easy to connect and disconnect. Package Includes: 1 Set Quick Release Connecter Coupling Note: 1. Please check as much as possible to make sure the item is the one that you need. 2. Please allow 0.5-1 inch difference due to manual measurement.(1 inch=2.54cm) 3. Due to the light and screen difference, the item's color may be slightly different from the pictures. Please kindly understand.