First generation door (left) vs second generation door (right)

The second generation housing is an evolution of the previous design, adding improvements to strength and decreasing size. In order to make these improvements, we increased the size of the battery door. Due to this change, the second generation battery door will not fit into existing first generation power meter housing. 

We will continue to offer replacement battery doors and o-rings for the first generation units using the latest stronger, improved materials. If you are in need of a replacement, please open up a support ticket with Stages Cycling or Stages Cycling Europe or visit your nearest Stages Cycling dealer for assistance.