This is a “Tunnel Extender” by SureFlap, a brand specializing in pet care products. It is specifically designed to extend the tunnel length of SureFlap microchip cat flaps, allowing for installation in thicker walls or doors. The product is compatible with both standard SureFlap microchip cat flaps and the SureFlap DualScan models. This extender is particularly useful for wall mounting to accommodate different wall thicknesses.
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