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https://www.openlearning.com/u..../floydconnolly-sm5jf
If you're planning to install a pet flap inside your uPVC door or glass panel, you'll need the help of an experienced cat flap installer. They can also help with more sophisticated models such as microchip pet flaps. DIY attempts to install a pet flap often result in problems such as draughts or low energy efficiency. Professional tradespeople can spare you from the stress and expense that comes with dealing with these pro