The Box Two E-Bike Cassette differentiates itself from its non-e-bike sibling by offering high gears with more teeth to withstand the rigors of modern E-Bike riding. Adding an extra tooth to each of the three highest gears provides increased durability and decreased wear by distributing the load over a larger area! All cogs are stamped from steel and subsequently, the larger ones are pinned to alloy spiders. Due to its provenance, this is, without a doubt, the most durable cassette in the range and perfect for any E-MTB. FEATURES - Our Most Durable Cassette - Steel Stamped Cogs - Lightweight Alloy Spiders - Ultra-Wide Ratio with Consistent Progression COMPATIBILITY - Box One Prime 9 Chain 126L DLC Black - Box Two Prime 9 126 Link Chain Nickel - Box Three Prime 9 126 Link Chain Polished - Box One Prime 9 Rear Derailleur - Box Two Prime 9 X-Wide Rear Derailleur Black - Box Three Prime 9 X-Wide Rear Derailleur Black - Box One Prime 9 Single Shifter Black - Box Two Prime 9 Single Shifter Black - Box Three Prime 9 Single Shifter Black