A sensor for a merchandise display security system for displaying and protecting an article of merchandise is provided. The security system includes a merchandise bracket configured to be secured to the article of merchandise and a sensor configured to releasably engage the merchandise bracket and to detect unauthorized removal of the merchandise bracket or the sensor from the article of merchandise. The sensor is configured to be releasably engaged with the merchandise bracket such that the sensor is removable from the merchandise bracket while the merchandise bracket remains secured to the article of merchandise.