They were 5/8 and 9/16s. Some have SFK on the tang and those ones according to Steve at the Invisible Edge were of an ever so slightly more wedge grind. I have had both varieties and can confirm this too.

Now I also know Wapi IIs were made which were a hollow ground, or comparatively more hollow, plastic handled variety. I think these were also 5/8, but may have been 11/16 or possibly even 6/8.

I love my Wapi and it never fails to provide a superb shave. Make sure you rescale it though! They are lethal otherwise!

French points are my favourite style. To add another note, virtually all Solingen blades with '42' on the tang are quite similar to Wapis in that they are quarter hollow with a French point. I have encountered a few, and they are usually always 9/16 although I have come across a couple of 7/16s.