Both the GL512 and GL522 include a 2-way, full-function remote control with a built-in back-lit grade display. You can do everything with the remote control that you can do at the laser keypad, up to 330 ft away from the laser even from the cab of a machine! The ability to make grade changes from anywhere on the job greatly reduces setup time and speeds operation. Verbal and visual communication errors are eliminated. The GL512 and 522 Grade Lasers retain all the other advantages of the GL400 series lasers with additional features and benefits.