Abstract: An electromagnetic valve for a vehicle gas cylinder, said valve comprising: a valve body; an external thread section of the valve body, that can be screwed into an internal thread on the gas cylinder; a section of the valve body protruding into the gas cylinder; a shut-off piston; and electromagnetic control elements which can be used to displace the shut-off piston from a conducting position into a closed position. The valve body comprises a cavity for receiving the shut-off piston and the control elements, said cavity being located inside the thread section and/or in the section of the valve body protruding into the gas cylinder. In order to simplify the disassembly and assembly of one such valve, the mouth of the cavity is arranged on the head end of the valve body located outside the gas cylinder. The shut-off piston and the electromagnetic control elements can be inserted into the cavity through the mouth thereof.