This adaptor ring will convert the EU and US standard lamp shades from their 40mm size to suit the 27mm UK light fittings.  I have printed it from PETG for better resilience and slightly better heat proofing, ABS or ASA would also be suitable. This will be suitable for LED lamps, but I would not recommend using it for traditional hot filament lamps. I scaled this model vertically in the slicer as the original was not suitable for thicker fittings, If its too thin for your lampshade scale higher it vertically to fit.