Box beam, I-beam and torpedo levels are levelling tools that check for surface level alignment and are used primarily in construction, carpentry, electrical installations, plumbing, and other applications. Box beams are box-shaped levels with handles or grips towards the center to make it easier to hold and use bubbles or spirit to determine surface levels. I-beam levels are used to verify the trueness of I beams in construction, while torpedo levels are smaller in design and can be used in tight spaces.