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MPF Printable version

https://www.controlbooth.com/wiki/MPF

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Medium PreFocus. Referring to a P28s socket or lamp base type, often used in 6" Fresnels (ex: 500W BTL) and radial ERSs (ex: 750W EGG).
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(A slightly ambiguous term, as the "M" could also stand for Mogul PreFocus, P40s.)