Fitting as follows; FS39000047000010 - Modular left arm bolts - suits 2017 and beyond modular cranks with extractor bolt on drive side and retainer bolt on left hand side - this is the left hand bolt - 24mm Spindle modular cranks FSCB390-2069 - black crank bolt for Omega and gamma drive 19mm spindle cranks with pinch bolt design left arm FSCB390-2067 - Silver crank bolt for Omega and gamma drive 19mm spindle cranks with pinch bolt design left arm FSCB390-2082 ML140 M18 Left Arm Crank Bolt Black crank bolt for alloy Mega Exo cranksets - Energy - Gossamer - Afterburner - V-Drive - Comet M/exo W/pinch bolt