Impact crank is made of 7075-T651 aluminum alloy, which allows the crank to have a strong rigidity. At the same time, the weight can also be much light. We pursue the perfect metal process, and the process is 100% CNC machining and manufacturing, precise control of all matching sizes and matching tooth profiles. Impact crank set uses a 30mm spindle with a unique 4-arm tooth chainring, The circular connection design can achieve a better GXP system's power transmission and impact strength. Material: high-strength aluminum alloy 7075-T651.We will offer help to resolve your problems as fast as possible. This item is in the category "Sporting Goods\Cycling\Bicycle Components & Parts\Cranksets". The seller is "bidnow4u2008" and is located in this country: CN.