This video explains how to install a Sureflap microchip pet door into a patio pet door.
The Sureflap PET door will fit the medium size patio pet door and the Sureflap CAT door will fit the small size patio pet door.
Please note customisation is required to complete this and it is done at your own risk, Your warranty will be voided once you do any sort of customisation to the pet door. This article is for information purposes only.