Komatsu Excavator Glass #20Y-53-11520 - #20Y-53-11611 KOMATSU Excavator Windows 8, 10-11 Series UPPER and LOWER Windshield. Offered in 1/4", 3/8" & 1/2" CLEAR POLYCARBONATE - SUPERCOAT™ BOTH SIDES. Lead time: 25-30 days - Made to order. To buy both upper and lower windows, add one window to your cart then add the second as a separate purchase. Not sure what thickness to get? Click here for info.