this is a spin off from the famous dog collar to lead one handed connector, one part is fitted to the hanger and the other to the hay bag and when refilling the hay bay you just lift it up and the magnet pulls the connector into the housing and locks it in, one handed operation. These make like easier for people with problems with their hands or while wering gloves, no more holding up the bag with one hand and tying it up with the other hand.