Thomson downhill alloy riser bar using aerospace technology materials and standards in their components thomson only design a product once they have learned everything about its function and dynamics only then can they know what is necessary to create a thomson features 780mm wide 12mm of rise 6 of backsweep and 4 of upsweep built using 7050 aluminum alloy for strength and long life 65mm wide clamping area to fit the thomson direct mount stem giving you the most torsional stiffness of