Exmark 103-6393, Exmark 103-6393-S, Exmark 103-6398, Exmark 103-6403, Exmark 103-6383, Exmark 103-6403-S, Exmark 103-6383-S, Exmark 103-6398-S, Exmark 116-5174, Exmark 116-5174-SExmark Lazer Z, Serial No. 540,000 and higher; Requires 3 for 60" deckLength: 20 1/2 ", Packaging Type: Branded label, Center Hole: 15/16 ", Width: 3 ", Thickness: .203 "