Goniometer Dimensions 12 Inch Material Plastic Scale Increments 0 - 360 Degree Head with Three ISOM Scales UNSPSC Code 42182701 Units of Measure Inches and Centimeters Clear plastic permits observation of joints axis of motion and its range of motion The 360 degree head has three scales calibrated to be used with the ISOM (International Standards of Measurement) system One arm has linear scale in inches and centimeters