Flatbed scanners and copy machines range in size from standard letter size (8.5"x11") to legal size and beyond. For example, a scanner used to scan architectural blueprints may be the size of several letter-size scanners. Because of their large size capacity and ability to scan thick objects, flatbed scanners are more versatile than sheet-fed scanners. However, they cannot automatically feed pages into the scanner, which means scanning multiple pages can be a time-consuming process. For this reason, some scanners and copy machines include both a flatbed scanning surface for large or thick objects, and an ADF for feeding multiple pages at once.