Package of 5 hinges. Offset pin allows more realistic door movement. With flaps allows gap for air to pass over the flap from underneath which in many applications is more scale and more efficient. Each hinge pad is approximately 12mm x 16mm. May be screwed or sewn (through factory pre-drilled holes) to surface. This hinge has several options for pushrod connections. Hole size is about .06" or 1.5mm, may be enlarged to suit.