Due to State and Federal Law, we sell Syringes and Needles only to the Medical Facilities. The integral absolute vertical and horizontal levels are permanently incorporated into the digital goniometer arm * Goniometer reads 0-180 degrees on LCD screen * Has ability to freeze angle measurement * Powered by 1 9V battery * Goniometer exterior is powder-coated steel with inch/cm marks screened onto arms * Digital angle reached in center * Horizontal and vertical levels to indicate level or plumb starting point *