NOS?

[Olliepen]

Erm - I'm pretty new to this whole retro bike thing, but without wanting to sound like a complete tool, what on earth does NOS mean?

 

[Thorpie]

New Old Stock! Took me a while too

 

[Corduroyboy]

NOS = New Old Stock
i.e. something that is old (and likely out of production) but unused, hence new.

Edit: I knew that as I typed, someone would beat me to it!

 

[ededwards]

Nasty Old S*** is a handy alternative