Endura Flap Thermo Panel 3e Window Mount Dog & Cat Door, Medium, 34-37-in W, Silver; Your pal will have the perfect window of opportunity to get outside with the Endura Flap Thermo Panel 3e Window Mount Dog and Cat Door. This premium medium pet door is specifically made for sash windows that slide up and down. The energy-efficient flap and dual-paned glass help provide superior insulation and protection from hot or cold weather. It’s constructed with sturdy and durable aluminum framing for long-lasting use. And the best part—no tools are required for installation. It’s a great option for a rental property or vacation home that has a furry friend who would like to come and go as he pleases!