A magnet unit is provided with a solenoid with a coil whose core is attached in a recess on the front side of a base, with a movable anchor activated by a recoil spring with a valve closing element and with a protective cap attached on a shoulder of the base within which the anchor and the solenoid are located, with a first end of the coil of the solenoid being led to a connecting contact located on the other front side of the base, the shoulder having, on its side facing away from the base, a circumferential annular flange located inside the protective cap, enclosing and protruding over the front surface of the shoulder and a second end of the coil being attached on the front surface.