Not on my box blade, but I do have one on my angle blade. I do not use it to set the grade but since my tractor is rarely level, I use it to be "near" level" and which direction. I want a little bit of slope cut in. Once I get the initial grade, then I wait for the rains and finish up based on what the rains indicate. This is one I got from an RV dealer that is intended to be mounted permanently on the outside of the trailer and always exposed to the elements, so mine is too. I put it where I can see it from the seat.