Can someone with an Eimac catalog reference a tube # 7527? Not certain if this is the industral version of the 3-400. Would appreciate any assistance. Ron W2CQM New York City -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com