blue collar
Blue collar does NOT simply refer to working class people. Blue collar workers are working class people whose jobs consist of MANUAL labor.
A white collar worker may also be a member of the working class. In some cases white collar workers make less money than blue collar workers.
A white collar worker may also be a member of the working class. In some cases white collar workers make less money than blue collar workers.
Example:
Construction laborers are blue collar workers.
Construction laborers are blue collar workers.