Description: Quick connectors for air piping, polyurethane tubing, pneumatic tools, etc. Used to connect threaded pipe and hose. Premium brass construction, nickel plated finish for rust and corrosion resistance; easy installation and maintenance, very safe and reliable for work. Simple to use, just slide back nut collar and insert fitting, then slide back to lock in the connector. Enables tools and air piping to be quickly connected / disconnected, which reduces accidental air line disconnection. These fittings are compatible with BSP fittings and UK style couplings. Specification: Material: Brass Color: As pictures showed Size: #1 - Outer diameter 6mm, inner diameter 4mm, for 12mm wrench #2 - Outer diameter 8mm, inner diameter 5.5mm, for 13mm wrench #3 - Outer diameter 10mm, inner diameter 6.5mm, for 15mm wrench #4 - Outer diameter 12mm, inner diameter 8mm, for 17mm wrench #5 - Outer diameter 16mm, inner diameter 12mm, for 22mm wrench Package Includes: 1 Piece pipe fitting(2 Pack) Note: To use of hoses and hose joints, please pay attention to the following points: (1)For avoid the mechanical device on the pipeline interference, hose piping design should ensure that the assembly and dismantling of pipeline space. (2)Use compressed air to clean impurities in pipe and fittings. (3)Pipe arrangement can be neat and orderly, user could numbered and bundled in groups, helpful for check later. (4)Hose length should be moderate, the bending part should not be too close to the joints in order to avoid leakage and hose twist.