Forged Alloy Arms 170 lengths Levatime II X-Spider/Rings | Simplified X-Rings w/Steel bolts 50/34 | 11sp M30 Alloy Spindle | 30MM DRIVE / 28MM NonDRIVE 8mm Alloy Main crank bolt for Install/Self-Extract Weight : 800g +/- (172.5 with 50/34) Q-Factor : 147mm 2X CHAINLINE : 44.5mm | 1X CHAINLINE : 45.5mm