This item is fixed to your Horse Trailer Grooms Door or Horsebox Access Door to allow you to swing the door open and secure it in the open position.   The door retainer set comprises of a Male/Female Plastic & Rubber pieces.   One piece of the set is mounted to your door and the other to your bodywork, when you open the door fully the male and female engage together and the door is held in the open position.   No more frustrating moments of that door swinging closed behind you.   Once engaged and the door is secured in the open position,  to close the door simply tug and it releases automatically, that simple.   The set is suitable for use on most Horse Trailer and Horsebox Doors. Simply affix using your own screws suitable for the surface being mounted to.   A good quality product that is fully weatherproof.