An IP rating is an international standard for rating how dust and water resistant a construction laser is.  Most all construction lasers have an IP rating.

The IP rating is followed by two numbers, the first number is for dust protection and the second number for water protection.  The higher the number more it can handle.  Ratings are 1 to 8.

I think it is important to emphasize that no mater what your lower IP number for water is, it is important to dry off your construction laser berfore storing it in the carrying case.

Listed below are a few examples of laser that have good IP dust & water IP numbers:

   Leica Rugby 610 IP 67
   Leica Rugby 620 IP 67
   Leica Rugby 640 IP 67
   Leica Rugby 810 IP 68
   Leica Rugby 820 IP 68
   Leica Rugby 840 IP 68
   Leica Piper 100/200 IP X8
   Leica Rugby 870 IP 68