Bofors/Nexter Bonus
155 BONUS is a 155 mm artillery cluster round, developed in cooperation between Bofors of Sweden and Nexter of France, designed for a long range, indirect fire top attack role against armoured vehicles. The BONUS base bleed carrier shell contains two submunitions, which descend over the battlefield on winglets and attack hardened targets with explosively formed penetrator warheads. Design. 155 BONUS is a 155 mm NATO artillery round that consists of a heavy artillery projectile containing two autonomous, sensor-fused, fire-and-forget submunitions. After the submunition is released it opens two winglets. While descending, the submunition  rotates, scanning the area below with multi-frequency infrared sensors that compares the detected vehicles with a programmable target database. The submunitions each contain a high-penetration EFP warhead for use against even heavy armoured fighting vehicles like main battle tanks. When fired from a 52-caliber barrel, a BONUS shell can travel up to . Competing systems. BONUS is very similar to the German SMArt 155 system; SMArt 155 descends on a parachute rather than a system of winglets. The United States developed the similar M898 SADARM system (which also descended on a ballute to attack the top surfaces of  armoured vehicles), but this was discontinued in favour of the GPS guided M982 Excalibur round. US artillery largely deploys the M712 Copperhead laser-guided round for the anti-tank role.