I have always thought the standard was 3 inches also. Just seems to be more of them at that length around. The DD's are about 3 1/2 I think and I remember some doosey cuts when I would shave across the grain with the longer spikes the first few times I used them.

Some guy is making little 2 inch blades these days in razors that look like pocket knives and I have honed a few of them finding them really difficult to shave with. Simply the size and the point on them with the thick scales make them difficult to hone, strop and shave with. Don't know if any of you have tried blades like this.

Have fun,

Lynn