The model 66 is the deeper drop of the two standard drop bars (64 & 66), and it's not that deeper. At the tubing end, it has a 24.0mm outer diameter and a 1.59mm wall thickness. The wall thickness will vary between the ends, because of bends and bulges in the bar. A 119mm long sleeve at the center of the bar builds out its diameter out to the 26.4mm needed for Cinelli stems. The centermost 39mm of the sleeve is knurled to give the stem additional grip. The straight area of the top section is 250mm long. The front face of the bar's top section and the forward curve has a groove pressed into it. This trough is to recess the brake/shift cables if Aero brake/shift levers are used. The drop, center to center, of the 66 is 158mm and the length of the flat is about 4.5" (115mm). The 66 is Clear anodized to a Silver color and available in three widths 40 cm, 42 cm, or 44. The weight of a 42 cm version of the 66 is 332.5 grams. Made in Italy.