AMAZING difference in his skin after a week with hypafix vs opsite. #1 was that he never complained of itching. #2 was when we removed it his arm looks like nothing was ever there. Our technique was this: sensor in (the sensor tape doesn't seem to bother him). Piece of hypafix under the transmitter. Piece of hypafix over the front of the sensor and over the connection of the sensor and transmitter and one piece over everything. No rash, no redness, no oozing skin. Nothing.