A regulator device (200) for a watch movement has (a) an inertial element (11) of a resonator (10) of inertia I, pivoted about a first axis (A1) and inscribed within a cylinder of diameter D centered on the first axis; (b) an escapement mobile (30) of inertia I3, pivoted about a second axis (A3) and inscribed within a cylinder of diameter D3 centered on the second axis; and (c) a blocking member having (i) a first blocking lever mobile (20a) of inertia I2a, pivoted about a third axis (A2a) and inscribed within a cylinder of diameter D2a centered on the third axis; and (ii) a second blocking lever mobile (20b) of inertia I2b, pivoted about a fourth axis (A2b), inscribed within a cylinder of diameter D2b centered on the fourth axis, the axes (A3, A2a, A2b) contained within a cylinder centered on the first axis (A1) and of diameter D′