Thermo Sash 3e Cat Door for Sash Windows Pet Doors A locking cover is included

A locking cover is included to close the opening when you want the door secured

you can add it here

The telescoping aluminum tunnel is a defining part of that experience

The extra long telescoping aluminum tunnel is sized specifically for thicker wall builds

It secures the locking cover in place

Thermo Sash 3e Cat Door for Sash Windows Pet Doors A locking cover is includedThis insert is built specifically for vertical sliding windows, allowing you to add a pet door without cutting into walls or doors. It sits cleanly within the window track, preserving the look and function of your home. Quick Setup No CommitmentThe spring loaded design holds the panel in place using pressure within the track, so installation is fast and removal is just as easy. This makes it especially useful for renters or anyone who wants