Abstract: A car wash includes a frame, a guide rail device for moving the car to be washed, and a cleaning apparatus. The cleaning apparatus includes a pair of first cleaning mechanisms and a pair of second cleaning mechanisms. Each of the first cleaning mechanism and the second cleaning mechanisms includes a pivotal frame, a cleaning unit attached to the pivotal frame, and a return unit for returning the pivotal frame to its initial position. The pivotal frames are returned to their position by gravity.

Abstract: A safety helmet includes a shell body adapted to be worn on the head of the user. The shell body has an outer shell surface and an inner shell surface opposite to the outer shell surface. The shell body is formed with a plurality of ventilation holes that extend from the inner shell surface through the outer shell surface. Each ventilation hole has a hole axis that is inclined relative to a horizontal plane. Each ventilation hole is further confined by an upper hole-confining wall portion and a lower hole-confining wall portion that is disposed below the upper hole-confining wall portion relative to the hole axis. Each ventilation hole has an inner hole end proximate to the inner shell surface, and an outer hole end proximate to the outer shell surface. The upper hole-confining wall portion is disposed below the lower hole-confining wall portion relative to the horizontal plane.