International ServiceMaster Inc, ISI In the mid-1950s ISI signed an import agreement with Mullard of Great Britain that also licensed IEC to use the Mullard name in the US. As early as 1955 they became prominent advertisers in radio magazines as distributors of Mullard tubes.
ISI IEC later acquired El Menco for their capacitor lines, and used the brand to rebrand tubes made in Japan for sale in the US. Ca. 1972, the Grossman brothers had a falling out. One left to found ICC (International Components Corp), and IEC soon fell to bankruptcy.
