Provides comfortable access across wider doors and walls Tunnel for extending the sleeve between interior and exterior frames when fitting the PetSafe Deluxe 4Way Manual Locking Cat Flap and Microchip Cat Door to doors and walls thicker than 50mm. Features & Benefits Fits the 4Way Manual Locking and Microchip Cat Door Each tunnel extends sleeve by 50mm Multiple tunnels clip together for increased depth Strong and durable plastic Provides more comfortable entry Supplied with 3 year warranty Technical Information Width 167mm Height 175mm Depth 60mm extends sleeve by 50mm Compatibility PetSafe Delux 4Way Manual Locking Cat Flap PPA1916732 and Microchip Cat Door PPA1916145 Material Plastic Colour White or Brown Fitting and Usage Fitting couldnt be easier and no tools are required. Simply push the wider face of the tunnel over the preceding and secure in place with a little glue.