"This is the best solution that I found for adding a pet door to a Pella slider. Overall very happy with the product and installation. Large-tall works well for our English Foxhounds. It has even stood up to the larger of the dogs (80 lbs) banging into it as he learns. He's also not that graceful. Sigh.
Some thoughts about installation, based on my experience:
1) I needed to make two extra trips to Home Depot, once for L-brackets and screws necessary to install to the frame, and a second time to acquire longer bolts for the latch mechanism, reinforcing plates because the latch mechanism winds up in a really weak part of the door, and a second bolt for extra security. I used larger L-brackets (1.5 or 2") on the top and bottom (one each, where the panel meets the door), then two smaller L-brackets on the side to secure the product to the door frame and keep it from flexing. Make sure that the brackets are small enough so that you don't drill into the glass! Your experience may vary.
2) The weatherstripping isn't quite long enough. I need another half foot or so for the top. It also will need to be caulked or weathersealed on the side against the door frame, as air still comes in around it.
3) The rubber air seal strip/sweep is a challenge to install on this particular model of door. I would suggest installing it as a first step. Not sure how I am going to do this without removing the panel.
All that being said, I wish that it was a touch sturdier, and that it was offered with double-pane glass. Those two minor complaints aside, it has been a really good purchase.
And like all other new things, make sure you give your pets time to adjust to it."
