1、Sealed and airtight, the air pipe can be inserted and removed very often. 2、With adjustable gas amounts,you can choose the most suitable gas amounts. 3、By screwing on the laser head, insert the air pipe connected to the air pump or air compressor. 4、When cutting flammable materials such as leather and wood, increasing the amount of gas can increase the cutting speed, prevent fire, and improve the quality of the cut surface. 5、The nozzle is made of premium material, sturdy and has long service life. Features: Sealed and airtight, the air pipe can be inserted and removed very often. With adjustable gas amounts,you can choose the most suitable gas amounts. By screwing on the laser head, insert the air pipe connected to the air pump or air compressor. When cutting flammable materials such as leather and wood, increasing the amount of gas can increase the cutting speed, prevent fire, and improve the quality of the cut surface. The nozzle is  made of premium material, sturdy and has long service life. Specification: Material:Brass+Plastic Set Type:Air Pipe 6mm;Thread Dia.9.7; Unadjustable /Air Pipe 6mm;Thread M5;Adjustable/Air Pipe 6mm;Thread M6;Adjustable/Air Pipe 6mm;Thread Dia.9.7;Adjustable/Air Pipe 8mm;Thread 9.7;Adjustable(Optional) Package List: 1*Laser Machine Gas Valve Note: Prevent the smoke from entering the laser head during processing and contaminate the focusing mirror. Otherwise, the focusing mirror is smeared, it is hot and it is easy to burst. Therefore, if the nozzle is blocked or leaking, it should be replaced immediately.