A locking device has a band (4) provided with a locking element (9) on its one end, a housing (1), a rocker (2) turnably movable relative to the housing (1) and having an edge which in a closed position of the device applies pressure to the band (4) and stops the band (4) from movement, the locking element (9) provided on the end of the band (4) being engageable with the housing (1), a first unit for turning the rocker (2) and releasing the pressure on the band (4) so that the band (4) is released and can be moved but the locking element (9) can not disengage from the housing (1), and a second separate unit which, upon release of the pressure on the band (4) and application of an action to the second unit by a user, release the locking element (9) from the housing (1) in a next step so as to disengage the element from the housing (1) and to open the locking device.
