Hi Oz, I am sure you are right, They are the same size and specifications but from everything I have been told, it has to do with the fact they are for Pleo Rb and PleoWorld has the rights to these batteries, which means that you are going to have to use their batteries and not the equivalent , the egg battery, Otherwise they would be losing out money by having other sellers, ( such as myself) sell these batteries also, I once talked to Derek Dotson , and he wasn't worried that I sold the Egg batteries, because he knew the market for the new Rb gave Pleoworld exclusive rights to have the only batteries that would work in Pleo RB. If you look closely, you will see even though they "fit" into Pleo Rb, they don't work correctly and they sit up higer than the egg batteries, they knew exactly what they were doing when they made these, I have even had a couple of people buy Egg batterie from me thinking they would fit into their new Rb, and I had to refund their money telling them only the Brown Batteries work in Rb and vice a versa.
If they ever become available anywhere other than PleoWorld I will sell them here.
RedwoodsMama