... 1/2" 12.7mm x 12.7mm 16,17,18,19,20,21,22,23 5/8" x 5/8" ... 12.7mm 16,17,18,19,20,21 1-1/2" x 1-1/2" 38mm x 38mm 14,15,16,17,18 ... 2.0mm,2.5mm,1.65mm 3" x 3" 75mm x 756mm 2.67mm,2.41mm,2.11mm,1.83mm,1.65mm 2" x 4" 50mm x 100mm 2.11mm,2 ... .5mm 4" x 4" 100mm x 100mm 2.0mm,2 ... In inch In metric unit(mm) 1/2" x 1/2" 12.7mm x 12.7mm 16,17,18 ...