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UPVC Door Handles Replacement Guide Replacing door handles made of upvc is a straightforward DIY project once you have the correct measurements. These measurements include the distance between the backplate of the handle's fixing centres (sometimes referred to as PZ) and the centre of the key hole. The most popular uPVC handle is made up of two inline levers. One is internal and the other exterior, connected via a spindle. They operate the multipoint lock found on uPVC