GENERAL 824 Mini Digital Protractor, Lithium-Ion Battery, Digital Display

Accurately sets blade angles on lathes, miter, band, table, chop and circular saws, easily adjust the saw blade angles to any angle you want, strong magnets hidden inside the bottom of the device securely attaches the 824 to saw blades, displayed value always shows right side up, whether the unit is upside down or not, arrow sign indicates the rotating direction, 0.1 resolution with 180 measuring range. Power source (2) CR2032 batteries included.