BIBISTORE Automatic Greenhouse Vent Opener with Two Springs Solar Powered Auto Window Opener for Hothouse&Cold Frame Greenhouse Acessories-Lifts 15.4 Lbs

I am thrilled with these venting arms. I built 2 cold frames and installed one lift in each. The top (light) is made out of 8mm polycarbonate. So, they are fairly light. Final results were awesome. You cannot do cold frame gardening without these unless you have nothing better to do than monitor outside temperatures and continually adjust your light throughout the day.The brackets were fairly easy to install. They sit inside my cold frames and I was not inclined to stand them on edge without assistance to install. Measure and drilling was a little tricky.It was a cool day here in the mountains when I finished. Outside temperature was about 55. Inside my cold frame was probably 70ish. You can see from the picture that the frames are partially open.

We used one of these vent openers on each roof window on our greenhouse last summer and it worked very well. We left it installed during the winter and this spring it failed to work at all so we purchased replacements. These work great but don't leave them out in extreme winter temps or you will need to replace them the next growing season.

Screws way to short and some of the plates they install into not tapped to take screws. Screws should be 1/4 longer. I should have returned but will make work somehow.

I was pretty skeptical when ordering these. But they actually work very well. We've had them on our green house now for just over a week and we've watched them function very nicely with the temperature. The only reason I didn't give them a 5-Star is because the instructions don't really tell you how to adjust them to start with. We've found that the best setting for our application was to screw them in until the threads are just coming out of the top.

You have to ROTATE the T-tube so it points in the same direction in my photo. Run the black rod through the bolt and into the T-tube. Insert the pin and slightly bend the legs apart, so it holds it in place. Hold the top and bottom open, against the force of the spring. Screw the threaded part of the black rod halfway down the threads. When you let it go, the spring will compress the black rod. Tighten or loosen it to adjust the temp it opens.Most of the bad reviews are from the instructions repeatedly saying to "note the position of the T-tube", when you have to rotate it 180 for the vent to function.This manufacturer can copy my instructions and picture if the want to send me some cool free stuff.

I have a two window cold-frame. Each sash weighing 20 pounds, I ordered two BIBISTORE Auto Vent Greenhouse openers each rated for 30 pounds of lift.I assembled and mounted the devices to my cold-frame. No obstructions. Although the inside temperature exceeded 98° the cylinder plungers on the openers remained static with no movement at all. I waited all afternoon to see when they would activate. It got hotter inside but nothing happened.The probability of two hydraulic cylinders failing seems very unlikely, but they are not working. I would appreciate any suggestions or advice on how to get the openers to work before I request a product return.

I don't think this part goes with my greenhouse. I made it work and once installed it works awesome to open the vent depending on the temperature of the day. I think this part needs some re-working as it did not go in my greenhouse easily. Either it needs to be thought out better or else not sold with this greenhouse. I'm happy to have it though because it's really hot in the greenhouse during the day and it will make the airflow happen without my involvement.

This will open and close based on temperature. Saves a lot of fuss and feathers