The Box One chain is protected by our dual-coating. We start with Nickel plating which aids in corrosion resistance and then top it off with the "Diamond-Like Carbon" layer. The DLC is as fancy as it sounds; a synthetic diamond nano-coating that turns up the volume on hardness, wear-resistance, and slickness. All Prime 9 chains have chamfered shifting edges, solid plates and solid pins to safeguard durability. Our unique inner link spacing is engineered to grab those modern wide/narrow chainrings. We chose to modernize the 9-speed platform due to the chain's spirited reputation. FEATURES - Our Best Performing Chain - Durable Dual-Coating - Includes Black Connecting Link COMPATIBILITY - Box One Prime 9 11-50T and also 12-50T eBike Cassette Black - Box Two Prime 9 11-50T and also 12-50T eBike Cassette Black - Box Three Prime 9 11-50T and also 12-50T eBike Cassette Black - 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 Shifter Black - Box Two Prime 9 Shifter Black - Box Three Prime 9 Shifter Black - Box Two Chainring - Box One Single Speed Aluminum Cogs - Box One Single Speed Chromoly Cogs - Box Two Freewheel - Perfect for your 3/32" BMX Chainring