What's the noun for limiters? Here's the word you're looking for.
limit
A restriction; a bound beyond which one may not go.
(mathematics) A value to which a sequenceconverges. Equivalently, the common value of the upper limit and the lower limit of a sequence: if the upper and lower limits are different, then the sequence has no limit (i.e., does not converge).
(mathematics) Any of several abstractions of this concept of limit.
(category theory) The cone of a diagramthrough which any other cone of that same diagram can factor uniquely.
“Management has imposed a limitation on the scope of the audit.”
“We think of limitations as something to get rid of, and certainly, we should not cling voluntarily to any limitation that hinders our spiritual growth.”
“In addition, we have a weight limitation that is annotated on the back of the sheet.”
limiter
That which limits or confines.
(historical) A friar who had a license to beg within certain bounds.