Finnish to English Other Engineering (general)

A "rajapaketti" appears to be something that is used with valves, and is paired with a "toimilate" (= actuator).

Here is a customer's comment on a company's valve products:

"
Nykyisten rajapakettien laatu / kesto vs vanhat rajapaketit -- esim. osoitinkiekot haalistuvat ulkona, asento muuttuu tärisevissä paikoissa.
"

What is this item called in English?

Thanks