Install your PetSafe Electronic Pet Door in thicker walls easily with the Large Wall Extension Tunnel. Designed as a smartdoor connected accessory, this extension is essential for ensuring smooth operation of your large electronic pet door in interior or exterior walls. Each extension adds 2 3/4 inches to your tunnel, giving your pets extra space and maintaining proper tunnel engagement for safe and convenient passage. Constructed from durable plastic material, the extension is built to last while being lightweight for easy handling. Its modular design allows multiple extensions to be stacked for walls of varying thicknesses, giving you a precise flush tailored fit and a perfect secure fit for your Electronic Pet Door. The installation is straightforward, with a quick DIY setup and tool-free application, making it simple to adjust your tunnel length without compromising stability or safety. Compatible with the PetSafe Large Electronic Pet Door, this tunnel extension provides consistent, reliable access for pets of all sizes and supports multi-pet households. Whether for indoor or outdoor use, the extension ensures your pets can enjoy safe, easy passage every day while maintaining the energy efficiency and functionality of your electronic pet door.