What is correct: "multiple restrike" or "multiple restrikes"? In general: should a noun after "multiple" be in singular or plural?

What is correct: "multiple restrike" or "multiple restrikes"? In general: should a noun after "multiple" be in singular or plural? (One "restrike" or more "restrikes" after each other can appear in circuit-breakers when breaking small capacitive currents.)

Multiple should be followed by a plural and not a singular noun if you are referring to several copies of an object. For example:

Multiple buildings were damaged in the explosion.

You're forming a two-word adjective which describes something. There's no "s".

Multiple choice question.

Multiple choice questions.

Multiple choice exam.

Multiple product packaging.

Multiple seat aircraft.

Multiple restrike starter motor.

Multiple restrike fuses.

(Hyphen korner: Note that in each case, you can use a hyphen if you want (just as with any compound). So, for example multiple-choice exam. Makes no difference.)

Note - you could make up obscure, tortured, situations where the "choice" part IS A NOUN and the "multiple" is just an adjective. Something like this .. "in life she faced multiple choices at the same time" or "the lightning struck once, then restruck, then restruck again, so, we had multiple restrikes after the original strike." But those are just silly, of course.