Automatic vent opener Gas spring for greenhouse

1.Auto open and close adjusted by temperature 
2.No need Battery 
3.12 years factory,SGS,TUV PASS

Based on thermostat in which liquid greatly expands or shrinks depending on the temperature.

In the sun, the temperature increases in a hothouse, thermostat located there in is heated,

the fluid pushes the piston and the piston, in turn, opens the window.

At sunset and a decrease in temperature in the greenhouse in thermostat fluid is compressed,

and the ventilator closes under its own weight.

Thus pane rises to 45 centimeters.

This system enables automatic ventilation greenhouses begin airing a temperature of 16 �,and 25 �.

The maximum length of the stem rises at 30C.

                                                            03 & 04 details pf packing and usage