A manually-operated hair clipper (1), comprising a substantially elongated enclosure (2), which defines at one end a handle (3) and is provided, at the opposite end, with a working head (4), which comprises a body (5) for supporting a cutting blade assembly (6) and a motor assembly (7), means being provided for transmitting motion from the motor assembly (7) to the cutting blade assembly (6), at least one comb element (8), which is associated with the supporting body (5) so that it can slide along a direction for approach and spacing with respect to the cutting blade assembly (6) in order to adjust the cutting length, and at least first means (14, 15) for stopping the comb element (8) with respect to the supporting body (5).