The setup blocks can easily set the height of the fence, blades bits and other cutters according to the needs, which is faster and more accurate than using a combined ruler. Combine bars to setup 100s of measurements. Stack setup bars for a wide variation or sizes, or use on their own, work and measure quickly. Set up gauge blocks are all 3 inches long. Accurate saw gauge block set sizes 116, 332, 18 ,532 ,316 ,732 ,14 ,516 ,38 ,716, 1532, 12, 2332, 34, 1x2x3 Easytoread laser etched labels on each block. Fitted case included, so the combination square will be more tightly protected during transportation. 15 pcs Blocks Solid Aluminum Construction Black Anodized to better protect router bits and saws.