The Stokke® Xplory® stroller was not originally designed to be used with a sibling board, simply because it did not exist at the time. In response to customer feedback over the first years our product development team worked hard to come up with an add-on solution that would not compromise the safety or stability of the stroller. They found that this could only be achieved by modifying the chassis in a way which cannot be carried out retroactively, on earlier Stokke® Xplory® strollers. The Stokke® Xplory® Sibling Board was only introduced in October 2009 and it is therefore only compatible with Stokke® Xplory® strollers produced from that date on. To be more precise, it will fit on Stokke® Xplory® strollers with serial number 113464 and above. It goes without saying that it fits on all strollers of the new V3 model, launched in 2010.