A regulator device for a vehicle door window pane includes a lift arm connected to a door window pane and an equalizer arm rotatably connected to the lift arm, connected to the door and the door window pane. The lift arm includes a through-hole, a flange wall, and a protrusion that defines an annular clearance between the protrusion and the flange wall and protrudes by a greater amount. The equalizer arm includes a first arm in contact with the protrusion, and a second arm in contact with the other side of the lift arm. A rotational axial protrusion rotatably engaged in the through-hole is formed on one of the first and second arms, and a fixing portion fixed to the rotational axial protrusion outside the through-hole is formed on the other of the first and second arms.