Sigma Automatic Roof Vent 16mm Operation is smooth and reliable

Operation is smooth and reliable thanks to the use of nylon bushings and solid shafts

Actual Dimensions: 42" x 42" inlet size

this fan is designed for consistent performance

These shutters are constructed with a heavy-duty extruded aluminum frame featuring precision-milled and strong welded corners for long-lasting durability

Price per sheet: $80

Sigma Automatic Roof Vent 16mm Operation is smooth and reliablePlease note: this window only fits Sigma Greenhouse models. Supercharge your Sigma Greenhouse with the Planta Sigma Automatic Roof Vent. Improve air circulation by bringing in the fresh outside breeze, keeping your plants healthy and disease free. The automatic roof vent is heat activated, which requires no electrical power or programming. This function ensures that hot air escapes during the day, preventing shrivelling or withering of your plants.