deskthority

I'm new to the vintage keyboard collecting but I've been using various keyboards for years (pre-model F days). Been getting tired of the keyboards supplied with systems for some time and have gone back to the Model M's I used years ago. I recently purchased a UK Model M with Blue/Grey keycaps and assumed they were added on aftermarket, but now I'm not sure. The model number is a 1391446, which I haven't been able to locate. Does anyone know if these keys were a standard IBM variant or an addon? Any other differences between this and a standard 1391406 would be appreciated. Seems to be a standard PS/2 as I've used it.

Could we get a close up of an individual cap, mainly the legends?

That will help tell if they are Unicomp, which they probably are.

I'd guess that the grey keycaps replaced the original alphanumeric keycaps that were color of the spacebar. The greys also replaced some originals in the F row + Esc that were originally same color as the modifiers.

i smell unicomp caps

Strange, I've never heard of another UK part number apart from 1406. And that cap colour DOES look off.

Almost certainly Unicomp caps, probably added to replace broken/worn old ones. Aside from the fact that the colour is that Unicomp blue/grey which I've never seen before 2003 or so, the fact that the SysRq legends are not in green but the Alt legend points to the keycaps not being made at the same time as the rest of the keyboard. The alignment of lettering is also different.

IBM had a lot of random part numbers for what were identical keyboards (the SSK in particular comes to mind) so it's possible that this is no different from a '1406. Another possibility is that this is a variant with custom keycaps, but since the keyboard does not have its original keycaps, we can't tell...

F4 and F9 also look to differ from the other F keys. Someone has definitely changed out keys on this board.

well this nice but I'd be very Interested in those (pre-model F days) keyboards if you have those. And yes those keycaps are replacements.