The Bugaboo Donkey 5 Duo extension set complete gives you the freedom to transform your Bugaboo Donkey 5 Mono into a side by side double stroller. Combine this box with the Bugaboo Donkey 5 base to create a complete stroller for two children of different ages. This extension set comes with all the elements to make your Bugaboo Donkey 5 ready for your growing family, including the sun canopy fabric.