Functions of wind hole: Excluding scraps Reducing noise Cooling purposes Core Thickness: 1.8mm Turbo Wave Saw Blade For Granite or Other Material Item Number Outer Diameter Hole Diameter Segment Dimension INCHES Metric (MM) INCHES Metric (MM) Hc0101201 4" 105 5/8"/20/7/8" 16/20/22.23 2.6? Hc0101202 4.3" 110 5/8"/20/7/8" 16/20/22.23 2.6? Hc0101203 4.5" 115 20/7/8" 20/22.23 2.6? Hc0101204 5" 125 20/7/8" 20/22.23 2.6?.3 Hc0101205 6" 150 20/7/8" 20/22.23 2.8? Hc0101206 7" 180 7/8"/1"/11/5" 22.23/25.4/30 3.0? Hc0101207 8" 200 7/8"/1"/11/5" 22.23/25.4/30 3.1? Hc0101208 9" 230 7/8"/1"/11/5"/2" 22.23/25.4/30/50 3.1?