Repeatability is defined as the ability to obtain the same results in multiple measurements under the same conditions. Repeatability is one of the most important things to consider when purchasing any type of measurement instrument since non-repeatability renders any measurement useless. It is no different with a laser shaft alignment system. No matter how easy a tool claims to be if it’s not repeatable then it is not easy to use, you will get frustrated and you have good reason. Repeatability should be achievable by any person who picks up the tool and at any rotational position around the coupling. A good laser alignment system should not have to measure the exact same place in order to achieve repeatable answers. If you cannot repeat readings at different rotational positions, how would you ever know which one is correct?