The CPL 50 combines the functions of a cross-line laser and a three-beam point-to-point laser. It projects plumb and level lines and laser points up and down. The third point is formed by the intersection of the plumb and level lines.
This tool has three controls: a sliding switch on the side and two push buttons on top. The sliding switch turns the laser on and off and locks and unlocks the pendulum. The push buttons control the mode of operation (line options) and activate the pulse function needed for use with a detector.
The on/off switch has three positions: off with the pendulum locked, on with the pendulum locked, and on with the pendulum unlocked. (In most cases you'll use the tool with the pendulum unlocked so that the laser can level itself.) I don't care for the switch. It's so tight you could inadvertently change the tool's position while trying to turn it on.
Changing modes is a matter of pushing the line options button - once for a level line, twice for a plumb line, and three times for plumb and level at the same time. The plumb dots that project from the top and bottom of the laser are on whenever any of the beams are on.
The Agatec laser is self-leveling as long as it's positioned within 5 degree
of level. LEDs on the housing indicate whether the beams have come to level. When the pendulum is unlocked and the unit comes to level, the green LED shines steadily. If the pendulum can't come to level, the red LED flashes.
If you turn the unit on without unlocking the pendulum, the beams will project steadily and the green LED will flash to remind you that the beams are probably not level. The beams fan out 130 degree
horizontally and 160 degree
vertically.
Optional detector. The kit we tested came with an LS30 laser detector, which can detect a beam that can't be seen in the bright sunlight. To use the detector, the laser must be placed in "pulse" mode. The detector beeps when it gets to within about 2 inches of the laser beam. Arrows on the detector's screen guide the user to exact alignment. The precision is good - it seems to have a go/no-go variation of about 1/8 inch. Built-in bubbles on the side and top of the detector help to orient the tool approximately plumb and level. You can use a button to disable the beeping sound when the detector is close to the beam.
Both the laser and the detector are wrapped in a rubberized coating. Threads in the bottom of the laser (1/4 x 20) allow you to attach it to a camera tripod or to the universal mounting bracket that comes with the tool. The bracket spaces the laser off the floor so you can see the point from the down beam. It's tapped to fit on a surveyor's tripod and has a magnet for attaching the tool to steel studs and other metal surfaces. 
