Working class under this perhaps even better?

Usage examples of flatcap.

To tell the truth he was mean in fortunes and for the most part hankered about the coffeehouses and low taverns with crimps, ostlers, bookies, Paul's men, runners, flatcaps, waistcoateers, ladies of the bagnio and other rogues of the game or with a chanceable catchpole or a tipstaff often at nights till broad day of whom he picked up between his sackpossets much loose gossip.