Here are some definitions as I understand them. Please set me straight if I am off-base on anything. I'll be adding to this list as time allows.
Milled- cutting away of material from a cast or forged component. For instance, some Campagnolo crankarms have a milled groove running lengthwise
Laser Etched- is used to describe some logos on Campy and some other components. A laser lightly burns the metal to make an image.
NOS- New, old stock. Unmounted and unused components or frame. Will show no signs of use or wear, but may show evidence of shopwear which should be called out in the description.
NR- Nuovo Record, "New Record" a Campagnolo model of derailleur, headset, etc
Shopwear- light scuffs or abrasions caused by being moved around on a shelf, or in a bin for a long period of time. Usually associated with new, unused parts or perhaps a frame.
SL- Super Leggero, "Super Light" a Campagnolo model of pedals, seatposts and other components?
SR- Super Record, a Campagnolo model of derailleur, headset, etc
GS- Gran Sport, a Campagnolo model of component. There was an "original" version of Gran Sport and a later version called Nuovo Gran Sport. The Nuovo Gran Sport hubs were also called Nuovo Tipo, or Tipo.
BSC- British Standard Cycle, used to describe bottom bracket threads 1.37" x 24 tpi,
TPI- Threads Per Inch.
JPG- Pronounced JAY-peg, a type of picture image seen on the internet
Dural- An old fashioned way of saying aluminum alloy
BCD- Bolt Circle Diameter, a measurement that describes the diameter of an imaginary circle drawn through the center of each crank/chainring bolt hole. For example, Campagnolo NR and SR cranks have a 144 mm BCD.
NIB- New In Box
See Velo-Retro's Campagnolo timeline at www.velo-retro.com/
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