Clockwork movement for a wristwatch, comprising a kinematic chain including at least one belt (20, 21) for transmitting the movements and/or couples between at least two pulleys. The pulleys are held on the bottom plate or the bridges by ball bearings (151, 161, 171, 181). The movement is rewound by means of linear oscillating mass (14) charging four barrels (15, 16, 17, 18) through a couple distributor (40). The barrels are non-parallel to one another. The back cover is covered by inclined glasses (110, 120, 130) allowing the barrels, the linear oscillating mass and at least certain pulleys to be seen. The regulating organ (51) is removable.