Seal

The disclosure concerns a seal, in particular a rod seal for sealing an axially movable rod in a guide cylinder, in particular a piston seal for a pneumatically, electrically or hydraulically driven coating agent pump for pumping coating agent, having an annular sealing element for sealingly resting on a circumferential surface of an axially movable rod, and having at least one elastic annular pretensioning element, the annular pretensioning element surrounding the annular sealing element radially on the outside and pretensioning it radially to the inside. The disclosure provides an annular seal base body which externally surrounds and holds the sealing element and the pretensioning element. In addition, the disclosure also comprises an inverted variant in which the seal is arranged in an annular groove in a lateral surface of a piston and lies sealingly against the cylinder running surface.