Switching lenses mid shoot has never been easier the case logic dsl 102 luminosity lens exchange case not only protects an additional lens such as a canon ef 100 400mm or standard 70 200mm but the open configuration creates a secure exchange pouch to store the removed lens while attaching the spare avoid juggling balancing and exposing your precious gear to the elements with wire mouth construction that offers a third hand when replacing one lens with another comes with a tailored weather