Carbon Side Loader Bottle Cage or the Other Side Loader Bottle Cage. Since the Sideloader was designed for right side or right handed riders Aundel came out with the Other Side Loader Bottle Cage for the lefties out there. The Other Sideloader cage is a mirror image of the original so, of course, they both look great together and work well, too.
SideLoaders are for seat tube mount, right side entry; Other SideLoaders are for down tube mount, right side entry. Swap them with each other if you're a lefty… or want the extra clearance of non-drive side access.