This 30s attache case is made of card with imitation leather finish. Nothing special except it has a uk patent to one side of handle which Espacenet relates to a published patent by Charles William Cheney for the handle design. But the other side of the handle has DUREX impressed. Still trying to work out the connection!
it's about the content. https://www.google.ch/search?q=dure...YUKHaToD-UQ_AUICigB&biw=1120&bih=538&dpr=1.71 normally there should be place for one pair of socks, one pair of jockeys and a small towel as well.
This one was Unsold, and looks somewhat different from yours. But some aspects of the description are the same. (Same patent number, for example.) There's also a story related to it that might be totally imaginary. https://picclick.co.uk/Rare-Vintage-Small-Navy-Suitcase-Made-By-Durex-401256921917.html Another: https://www.worthpoint.com/worthopedia/vintage-rather-shabby-black-navy-251932996
I'm amazed at how many times the word Durex appears, they must have been a very diverse company originally. Found this lovely knife set and lots of reading glass cases, but not briefcases. But what is someone saying about themselves who has a phone case like this???