That's what I thought at first too zerksies but click on the other tabs at the top of the guitar page - it's a gold mine of info on JP's amps and effects
I'm a Zep bootleg collector(hundreds of shows in the collection)and his tone from around 70 to 72 is steller...my verdict is...he should have stayed w/ Hiwatts...now don't get me wrong I own a few Marshall's and I love em but just listen to a few shows(1-9-70 Royal Albert Hall on the DVD boxed set(Hiwatt)compared to (7-28-73 Madison Square Garden "Song Remains the Same"(Marshall)and the difference is apples to Oranges...if Page would have actually played the Orange amps (instead of slaving em)Zep could have been a successful band and maybe went somewhere