I have had many contractors ask me what is the difference in the Leica Rugby 610 Laser versus the Leica Rugby 640 Laser.  Both have a visible laser red diode, but the price between the two is different.

The Leica Rugby 610 laser is a simple one button self levelling, red diode laser that is horizontal only and the rotating head can not be stopped.  This laser is mainly used with a Leica Rod Eye Sensor, either the Basic or 140 classic.

The Leica Rugby 640 is both a horizontal, vertical and manual slope laser. The laser is a visible red diode, but the rotating head on the Rugby 640 can be stopped. the rotating head can be set to 0, 2, 5 and 10 rps.  Also the Leica Rugby 640 has a scanning feature of 10, 45 and 90 degrees.  A contractor can purchase a remote control for the Rugby 640.  I believe the remote control is agent feature for this laser, and works up to 650 diameter from the laser