The Cache bottle cage has a side entry (to accommodate all frame sizes) and is paired with a flip-up flap for left- or right-handed use or for mounting to the seat tube (where you need to reverse the entrance). For down tube mounting the design has been optimized for the recessed section on the Spark but will work with all bikes. One aspect we've paid particular attention to is water bottle retention, and our engineers have conducted extensive testing to ensure the bottle stays on the bike for when you need it.