I was called to a property in Chafford Hundred where the owner had seen videos on you tube about swapping cylinders on upvc doors,I had a look at the rear doors and the french doors on the property and the cylinders did protrude a bit out of the handle.I advised the owner to have ABS anti snap british standard cylinders fitted.These are very good cylinders with lots of security benefits to deter a thief. The owner was imprest with the cylinders and had them fitted giving him peace of mind.