What a small Royal Marines detachment adds to a base

How large would a Royal Marines detachment at a forward base be, and what would it do?

Perhaps 20-40 personnel, used for boarding, presence, medical support, and diplomatic engagement rather than as a large combat garrison.

A useful forward-base detachment might contain roughly 20 to 40 Royal Marines rather than a large combat battalion. The group could support boarding operations, local presence missions, and other routine tasks that require trained personnel on short notice. Marine medical skills would add practical value to both the base and regional engagement. A small band element could also help because ceremony and diplomacy let a forward force build relationships as well as display combat capability.