e*thirteen Helix Core cranks feature forged AL6066-T6 aluminum alloy arms and 24mm heat-treated chromoly spindle that offer Enduro strength and durability. Weight reduction features are designed into the mold to stay true to the strength and weight optimization with less CNC time and cost. Exemplifying cross compatibility, Helix Core Cranks can achieve both Boost and Super Boost chainlines, and perform equally well with both SRAM™ and Shimano™ 11 and 12-speed drivetrain systems. Equipped with a self-extractor bolt system, and creak-free proven Quick Connect interface, you get all the benefits of higher-end cranks without a heavy price tag.