This is a half circle spray whose head is directable which means that you can push the spike in the ground according to the lay of the hose, then swivel the spray-head to where you want it. Used up against a fence or near the edge of a border. This is a “barbed fitting” which means that the ½ inch (13mm) hoseline or Polytube fits directly to the spray – no need for connectors.  Typically 3 to 4 per hose-line.