The only design model in China, if you can find a similar model better than us, we will send you a sprayer for free. 

Automatic Air Lock Sprayer

Working pressure: 0.16-0.45MPa

Model: HY-2, HY-3

Based air pressure: 0.16-0.18MPa

Volume: HY-2 11L HY-3 16L

Maximum spray distance: 7_10m

Package: HY-2 44*22*62cm3 HY-3 44*41*62cm3

Weight
: HY-2 5.0kg HY-3 6.3kg

The advantage: 

1. After spraying liquid, self-locking device will automatically remind the user closes the spraying air lock switch, which allows the retention of the preset pressure for the next cycle

2. Users can expand spraying capacity according to your need. 
3. The liquid pressure inside the tank can pressure exceeds a predetermined value is automatically released when the excess pressure to ensure that over-pressure spray not be damaged. 
4. The sprayer spraying a range of 7-9 m, fine spray efficiency than ordinary spray 2 to 4 times
5. No fuel consumption, no emissions, no liquid leakage, no noise, vibration and high temperature, the entire sprayer open design, it is easy to find fault even with the point of failure, and easy maintenance.