As a starship class, frigates has been invented long before Aegis Prime's assembling, but current look of these ships is based on flagship's blueprints.
Frigate is armed by two long-range laser cannons, four short-range AA blasters and six very powerful laser sidecannons. Also, instead of landing pods, frigate is armed with sabotage pod that launches into a space and, by maneuvering, cutting into enemy ship's frame. Then the capsule uses it's noseplates to break bulkheads and bordering by powerful hydraulics. Then landing hatch opens, allowing the boarding squad to enter the hostile territory.