Comentarios: Must confirm the markings on the side of the pads being replaced before placing an order. There are 4 separate pad sizes, identified by markings 577, 579, 581 & 583. Pads must be replaced with the same pad sizes as originally installed. JLG part numbers have been issued for each of the pad sizes as follows: JLG P/N Original Pad Marking US03211 577 US03212 579 US03213 581 US03214 583