can somebody tell me what NOS means please
NOS is not
an acronym, an acronym is a word made up from the first letters of other words.
For example SHAPE
is a word and the name (acronym) for Supreme Headquarters Allied Powers Europe.
All the other answers viz NoS are correct.
Rk - abbreviation for Roadking!
Co-founder of a V-CC section, member South Eastern Road Club and owner of - 2005 Bianchi Reparto Corse (modern), 1985 Raleigh SBDU Pro Super, 1984 Raleigh LU Corsa, 1980 Allin Stan Butler Special, 1978 Ron Cooper, 1975 Bill Philbrook tourer, 2 x very early Roberts (mid/late 1960s), 1966 Raleigh Superbe Roadster, 1964 Allin Stan Butler Special Belgique, 1951 Hobbs of Barbican S/C, 1950 Hobbs of Barbican S/C, 1947 Hetchins Super Special, 1908 Centaur Featherweight. 1988 Specialized Stumpjumper.