Leonard Brown was a paper pusher at T.H.U.N.D.E.R., who wanted to be an agent, and agreed to wear the Thunder Belt, which gave him super strength and a dense body structure, but could only function for half an hour at a time, putting a large drain on his body. Still, while using it he was strong and mostly invulnerable to harm....
Dynamo #1 and #2 (August and October, 1966)
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Dynamo #3 and #4 (March and June, 1967)
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