The Cache cage features a side entry bottle design (to fit all frame sizes), married with a flippable wing for left or right handed use or for mounting on the seat tube (where you need to reverse entry).For downtube mounting the design has been optimized for the recessed section on the Spark but will work with all bikes. One area we paid particular attention to was bottle retention and our engineers conducted extensive testing to ensure that your bottle is kept on your bike for when you need it.Features:Side entry bottle cageFlippable wing for left or right handed useSide entryOptimized fit for recessed frame down tubesHigh bottle retentionSpecifications:Material: Nylon + Glass FiberWeight: 36g approx.Size: One sizeStandard: Side entry