At One Click Purchasing, we are your reliable source for the NSN part 400EM manufactured by Johnson Level And Tool Mfg Co Inc. We carry a wide range of popular NSN items on our website, including Square Combination like part number 400EM which is listed with the NSN 5210013650051 for easy identification. If you are interested in 400EM item, then take the advantage of our online RFQ service, or peruse our website as you see fit to find other items of interest that you may wish to learn more about.