Sensory unit for connection to a sensor housing, comprising a) a housing with a cap-, tube- or sleeve-like design and with a first housing opening, which can be directed to a medium to be analyzed and a second housing opening, b) at least one sensor element arranged in the housing comprising indicators and optionally indicator protectors, wherein the sensor element has a first side facing the first housing opening and a second side opposite the first housing opening, c) at least one protector element which is designed as a protector element membrane, d) a carrier element on which or at which the sensor element is arranged, with the second side of the sensor element contacting the carrier element, or the sensor element forming a unit with the carrier element, wherein the protector element is arranged in the region of the first housing opening between the at least one sensor element and the medium surrounding the sensor unit in such a way that the sensor element does not directly contact the medium, wherein the protector element in the region of the first housing opening is connected mechanically fixedly to the housing and the sensor element or detachably to the unit comprising sensor element and carrier element at a chamfer of the housing, which chamfer is arranged in the region of the first housing opening and is oriented towards the interior of the housing, wherein a gripping or covering of a peripheral region of the protector element by the chamfer is provided, and wherein the periphery of the protector element is arranged in a groove-shaped region arranged at the first housing opening and defined by the chamfer on the one hand and the support element or the unit of sensor element and support element on the other hand, and is pressed or pressed into such a region, and the groove-shaped region is defined by the housing chamfer and a press ring which is assigned to the housing chamfer and is arranged in the housing interior, and the carrier element or the unit comprising sensor element and carrier element is integrated into a lumen of the press ring, wherein a sealing and/or clamping element, in particular an O-ring, which effects the mechanical connection by pressing or pressing and can be inserted into the groove-shaped region is provided. a) a housing with a cap-, tube- or sleeve-like design and with a first housing opening, which can be directed to a medium to be analyzed and a second housing opening, b) at least one sensor element arranged in the housing comprising indicators and optionally indicator protectors, wherein the sensor element has a first side facing the first housing opening and a second side opposite the first housing opening, c) at least one protector element which is designed as a protector element membrane, d) a carrier element on which or at which the sensor element is arranged, with the second side of the sensor element contacting the carrier element, or the sensor element forming a unit with the carrier element, wherein the protector element is arranged in the region of the first housing opening between the at least one sensor element and the medium surrounding the sensor unit in such a way that the sensor element does not directly contact the medium, wherein the protector element in the region of the first housing opening is connected mechanically fixedly to the housing and the sensor element or detachably to the unit comprising sensor element and carrier element at a chamfer of the housing, which chamfer is arranged in the region of the first housing opening and is oriented towards the interior of the housing, wherein a gripping or covering of a peripheral region of the protector element by the chamfer is provided, and wherein the periphery of the protector element is arranged in a groove-shaped region arranged at the first housing opening and defined by the chamfer on the one hand and the support element or the unit of sensor element and support element on the other hand, and is pressed or pressed into such a region, and the groove-shaped region is defined by the housing chamfer and a press ring which is assigned to the housing chamfer and is arranged in the housing interior, and the carrier element or the unit comprising sensor element and carrier element is integrated into a lumen of the press ring, wherein a sealing and/or clamping element, in particular an O-ring, which effects the mechanical connection by pressing or pressing and can be inserted into the groove-shaped region is provided.