The orders -- from Peru, Finland and Germany -- are worth a total of about $21.5 million.
Peru's initial order, part of a modernization program for its LUPO-class frigates, will equip two ships with the company's Multi Ammunition Softkill System.
The contract includes an option for equipping two more frigates of this class within the next two years.
The German navy awarded Rheinmetall with another follow-on order for equipping its minesweepers with MASS.
Following immediate retrofitting in 2008 of two counter-mine vessels in response to an urgent operational requirement, two more vessels of the same class were equipped with MASS in 2009. Under the current order, two more counter-mine vessels will be equipped with a MASS two-launcher configuration with integrated detection unit.
Rheinmetall will retrofit six RAUMA-class missile boats for the Finnish navy.
MASS protects ships using advanced, sensor-guided missiles on the high seas and coastal waters -- as well as from asymmetric, terrorist-type threats -- by firing decoy rounds that lure incoming projectiles away from the intended target.