VEVOR Dog Door for Sliding Glass Door, 75 7/8"-80 11/16" Adjustable Height Doggy Door for Sliding Doors, Aluminum Frame Tempered Glass Pet Door with Hinge Structure Flap and Lock for Large-Sized Dogs

While the product description doesn't mention insulation, customers generally don't think it insulates well. One review mentions the flap lets in drafts.

This is the connecting rod that links the upper door to the lower door. If this answer does not resolve your current issue, please contact us again for assistance.

This door can slide left and right.

Based on the product description, it says easy installation and sliding into patio door track without tools. However, customers seem to have mixed reviews. Some report it as difficult to install and would recommend professional help, while others say it is easy.

While customer reviews are mixed, with some mentioning the flap is hard for pets to use, others note it is easy for their dogs to push open. The product description describes the flap as spacious for pets to enter and exit comfortably.