I didn't knew there were different sizes of walnuts. So far I had seen walnuts of same size - more or less, while some were bigger than the others but they couldn't be called different sized. That was till I saw these. The one on the right is a regular walnut and the one on the left is a smaller one. These are distinctly different than the regular ones, their shell is much softer and thinner - something like a cross between a peel and a shell. The good thing is that most of the times, the entire nut comes out in one piece. The shape is also different as can be seen here.