I have a few more of these fuzes and I never noticed the diference, but as you will see, mine are also different. Could these be all variants, "ersatz"? in your model, there are a few parts made of brass, and the powder channels seem to be lined with brass as well, in the two fuses below, there's no such thing, and they are mainly made of aluminum with less brass parts. They all seem to be graduated up to 130, and the one on the shell as well.