In principle, very similar device to Laser Ray Box, but emitting one laser ray since it contains one independent laser module. 

The beam is collimated by cylindrical lenses to be highly visible. 

Via attaching multiple Line Boxes, multi-beam source can be created. It is taped with magnetized foil, allowing intuitive attachment to a magnetic board or use in conjunction with sheets and models from Ray Optics Demonstration Set.

Set includes also battery box (2x1,5V, AA size), power supply and connecting cable for multiple Line Boxes. 

Specification: 

Laser type: Diode 

Wavelength: 635 nm 

Output Power / laser class: Pmax < 1 mW / 2 

Dimensions: 80 x 25 x 20 mm 

Power Supply requirements: 3V DC / 50 mA