A brake unit for a vehicle, in particular a rail vehicle, has a brake cylinder, a brake piston and a device for adjusting a clearance. The latter has two first stops that strike against each other when the brake unit is opened. One of the first stops is formed on a blocking element that is functionally connected to the brake piston. In order to be able to open the brake unit beyond the clearance, a blocking member is in engagement with the blocking element under the force of a pre-stressing spring. The blocking element is blocked by the blocking member when the first stops strike. Actuators displace the blocking member that is in engagement with the blocking element counter to a force of the pre-stressing spring into a position detached from the blocking element.