from the mating area 206 so that the shape of the sensor plate 120 does not align with the shape of the mating area 206 the closer the stopper walls 216 and or the retaining flanges 218 are positioned to the corners of the perimeter 207 the more space there can be for the sensor plate 120 to be inserted to contact the retainer springs 208 without being obstructed by the retaining flanges 218 or the stopper walls 216 fig3 is a top view of the probe 10 of fig1 illustrating the probe 10 with the sensor assembly 100 and the open junction box 200 assembled in one embodiment of the invention as illustrated in fig3 once the sensor assembly 110 is fully inserted through the opening 204 so the sensor plate 120 depresses the elastically deformable retainer springs 208 and the sensor plate 120 presses against the gasket 300 and or the mating area 206 including any rests 220 the sensor assembly 100 can be rotated into an assembled position locked under the retaining flanges 218 by rotating the sensor plate 120 in one direction until the sensor plate 120 corresponds and fits with the mating area 206 in the assembled locked position the sensor plate 120 is obstructed from rotating in one direction out of the assembled position by the stopper walls 216 as shown in fig3 the sensor plate 120 can be rotated counter clockwise to.