That is a bit of an odd one. No "made in." No patent info. No Gillette diamond.
Could this have been a model instead of a production run piece? Why would anyone knock off a Tech?
It could be a british made tech. I know the ones in canada and us both have a made in usa or canada stamp. Not sure about british though
Head lettering and shape is typical of Gillette's British style, handle is also correct. Baseplate though is firt sen by me and i own several Techs.
Maybe dissasemble it and take more pics of the baseplate so we can help.