The LVR 110V operable vent system is mercury free and designed to work with many style greenhouses.
The LVR Automatic Vent Opener is fastenened to the structure's glazing bar(s). Before purchasing the LVR Automatic Vent Opener, you'll need to identify which type you have: I-Frame or Tubular?
Below are examples of the differences:
Tubular Glazing Bar Example:
I-Frame Glazing Bar Example: