Hi all, I have this part for sale, I'm sure its for a headset, has NO threads at all, so I'm thinking would not be from a BB, would look to be a lower cup from some old model headset, is chrome plated with NO blemishes, the only marking is a C in a diamond, will do my best to give sizes that might help you determine what this item is, of what headset it maybe from, am asking US$30.00, this includes insured P&P and paypal fees........regards wayne davidson invers NZ..........
ID for where the steerer tube would run thru = 26.76mm the OD for where this would sit in the frame = 37.10mm the length of the step = 5.26mm overall height = 14.35mm overall diameter 41.10mm the outer showed edge tapers with a curve.