MPF Printable version

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).
View attachment 4158
View attachment 4159

(A slightly ambiguous term, as the "M" could also stand for Mogul PreFocus, P40s.)