Finally, a digital goniometer designed by therapists for therapists. This is the most cost effective and reliable digital goniometer on the market. It allows highly accurate, repeatable and reliable joint measurements. It contains dual 10 inch or 250 mm poly fiber blades with a center line and English and metric graduations. Transparent poly fiber blades permit easy location of joint axis and unobstructed observation of movement. Latex free hypoallergenic ploy fiber blades are easily sanitized after each use. From the “zero” setting it measures 360 degrees in both directions. Relative “zero” can be set at any point in an arc. It has a large LCD display that displays continuously as the blades are adjusted. Degrees are displayed in .05 degree increments (5 hundredths of a degree) and has an accuracy of +/- .5 degrees (half of a degree). It contains a “hold” function so you will never forget a measurement. It uses a 3V lithium ion battery that will last one year with normal use. Comes with one battery installed and one extra battery. Unit powers down after 5 minutes of nonuse.