Or to give a bit more detail, there are two common wood grip versions of the Diana 2 (or Original 2). The earlier one has a completely smooth grip, whereas the later one has pressed chequering on both sides, and machined ridges round the the grip edges. The third rarely seen version is characterised by having chequering on both grip faces and smooth grip edges, and is usually darker in colour than the other two versions. The lack of ridges is not easy to spot from a typical face-on photo unless you are specifically looking for them. It seems reasonable to assume that the rare version was a short lived transitional model that appeared between the other two, but there is no firm evidence for this.
A couple of other examples can be seen in the Vintage Airguns Gallery here
https://forum.vintageairgunsgallery....l-2/#post-4390