Pet Doors for Sash Windows
The Thermo Sash includes dual-pane, insulated, low "E" glass which is the highest performing glass available. It is standard on the Thermo Sash llle.

This glass unit is guaranteed for 10 years. The spring load design can be installed and removed in seconds. No tools need for installation. Exclusive Built-in "Anti-Whoops" allows for 3/4" change in adjustment range to allow for small measuring errors. Draft Stopper keeps air from coming in between the two windows. Adjustment ranges accommodate windows 22" - 43" wide in 3" increments. Track width must be at least 1".

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