Zpacks made these for a few years before but, didn't always list them on their website.

I kept this after selling my Duplex in case I ever decided decided to buy another. At this point, I'm ready to let it go.

This is fantastic for making the tent darker and for keeping condensation from dripping on you.

I dont know what it weighs but, it isn't much at all.

How it works:
Each corner of the insert, as well as the two center points which correspond with the roof peaks, has a small plastic toggle.

Each toggle corresponds with a loop that is pre-installed in the tent...or at least they were in mine.

Just attach it and be done. You can take it out everytime if you would like but, I just left it in.

Long Winded Modification:
When this is used as intended, the cords at the head and foot end of the tent are under the insert, which would allow condensation to fall into the tent instead of out through the mesh.

To combat this, I added a plastic toggle to the outside of the insert, which goes through the installed loop that the floor lifter would normally attach.

So that the floor lifter could still be attached, I installed extra loops to the interior side of the insert.

While I'm sure that I've made this sound way more complicated than it is, just know that you will love having this in your tent.

I've also purchased extra loops to made sure your install goes smoothly.

Please let know if you have any questions.