500mW Blue Laser 447nm Waterproof Adjust Focus Blue Laser Pointer Pointer Pen,$185

Features:

This blue laser pointer pen is well tested and high quality
This 500MW blue laser pointer pen is easily to use, only need to push the back button then you can see striking blue beam of light shoot forth. The blue laser pen can point at any targets, such as photos, blackboard, video monitors and so on
This waterproof laser pointer pen is the best choice for teachers, professors, doctors and so on
The 500MW blue laser pointer pen is clearly visible in the dark
This The 500MW blue laser pointer pen has very good waterproof properties, it can light match within 25 meters

http://www.lasershine.com/500mw-blue-laser-447nm-waterproof-adjust-focus-blue-laser-pointer-pointer-pen-1-x-18650-battery_p662.html