D5H D4H D5H XL D4H XL D4H III. • Pantograph wiper arm (dual arm). 517 527 D4HTSK II D5HTSK II D4HTSK III. 4S 4P 5P 5S 5A 4A. Cat wiper arms are designed to hold the wiper blades firmly against windshield and transmit the parallel motion to the wiper blades to clear the windshield.