The 3/8 x 24 version for solid spindle crank sets B. The Gun Drilled Hollow M12 x 1.25 version for our GDH spindle crank sets, and C. The 7/16 x 20 version for the old solid SS Crank spindle. A pair of Solid Flush Mount bolts weighs 36g, and a pair of the GDH Bolts weighs 40g / 1.4oz.
