Since we've been a southpaw from day one, Arundel's original Sideloader carbon bottle cage is not to our liking on our down tube. We steer with our left and reach with our right. The Sideloader is designed to be pulled from the left. So for us, the Sideloader would work as a seat tube-mounted cage, but not down tube. Hence the introduction of the Arundel OtherSideloader Water Bottle Cage. It's designed to be pulled from the right side on the down tube and from the left side on the seat tube.
And to satisfy our need to give truth in advertising, both Arundel's Sideloader and OtherSideloader are not true side-loading water bottle cages. This is to state that you do not pull them out or push them in a plane that is perpendicular to the down and seat tubes. They are more accurately called 3/4 loaders, as they are designed to have the user insert and remove the bottle in a direction that is halfway between perpendicular and parallel.
One drawback to buying the OtherSideloader online is you don't get to see the cool packaging that is printed backwards on purpose until you get the cage in your hands. The cage comes with a small cardboard backing that includes alloy bolts. There are two sets of holes for the alloy bolts to go through, high and low. Choose one. Weight of a single Arundel OtherSideloader Water Bottle Cage is 30g.
The OtherSideloader solved a design flaw on my wife's bike. The manufacturer located the screw holes so high on the down tube that a large capacity water bottle could not be removed from a standard cage without hitting the head tube of the bike with her hand. That problem no longer exists with the OtherSideloader.