The shimano 105 5800 11 speed road cassette is a high performance 11 speed cassette hyperglide ev sprockets have a computer designed tooth configuration with contoured shift gates resulting in a crisp smooth shift even under load the close ratio gearing allows a more efficient use of energy through finer cadence control the largest sprockets are mounted on a lightweight alloy carrier to reduce weight and increase rigidity as well as this all sprockets are cut away and drilled to further red