Fsa afterburner alloy mexo m 10 cranksetwith hollow forged arms and a forged 7050 spindle the afterburner double crankset represents cutting edge aluminium technology the double chainring version features a 38 24t profile to help you get up the steep climbs all rings are stamped from hardwearing 7075 aluminium and carry ramps and pins for slick shifting even under load features material spindle 7050 alloy chainrings 7075 alloy speed 10 bottom bracket mega exo hollow forged crank arms