Sensor

A sensor having a sensor housing (12), having a sensor holder (44) to which the sensor housing is fastened, and having an installation body (14) which has a receiver device (16) for the sensor holder (44) at one end of the installation body and which has an interior, wherein connector lines for the sensor are guided at the interior in the installation body, wherein the receiver device (16) is configured such that the sensor holder (44) is rotatable with respect to the installation body (14) and is adjustable by a telescopic extension or retraction or the sensor holder (44) is rotatable with respect to the installation body and tiltable with respect to the installation body, wherein the receiver device (16) has clamping elements (18) for the sensor holder (44), wherein the clamping elements (18) can be clamped tight by means of a cap nut (20) which engages into a thread (24) of the receiver device (16), wherein the cap nut (20) has a first sealing ring (30) at an opening (28), said first sealing ring contacting the sensor holder (44), and has a second sealing ring (34) at an oppositely disposed opening (32), said second sealing ring contacting the installation body (14), wherein the sealing rings (30, 34) are connected without joins to the cap nut (20) and an angle (α) greater than 90° is formed between an outer surface (36) of the first sealing ring (30) and an outer surface (38) of the sensor holder (44) or between an outer surface (40) of the second sealing ring (34) and an outer surface (42) of the installation body (14).