Dear Khun New,
The 1:160 / 1:150 N-Scale is correctly by Khun dragon. N-comes from the width of 9 mm of the track and is hence called Nine(9) Scale.
The 1:87 H0 Gauge Track is 16.5 mm in width.
H0 comes from the word "Half Original" whereas the O-Scale in the past when Maerklin started was 43.5 but now has settled at 1:48 Scale.