For Sumida product that was produced before the RoHS compliant movement began, an NP is added to the part number immediately after the inductor type, ie. CD54NP-100MC or CDRH5D18NP-220NC. For new product produced after RoHS compliant became a required industry standard the NP has been left off because RoHS compliant is the only way the part is manufactured, ie. CDRH8D43-150NC is RoHS compliant. The best way to confirm RoHS status of a device is to check our Product Details page for the green RoHS symbol. If available in both versions, the alternate part number will be noted on this page.