At One Click Purchasing, we are your reliable source for the NSN part 138-4P manufactured by Sikorsky Aircraft Corporation. We carry a wide range of popular NSN items on our website, including Stem Needle Valve like part number 138-4P which is listed with the NSN 4820016624518 for easy identification. If you are interested in 138-4P 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.