The BONUS is very similar in theory, design, and operation to the SADARM projectile developed by the U.S. The 155mm carries 2 submunitions the same as bonus, and the U.S. 8 inch SADARM carried 3 submunitions. The 8 inch used a standard M509 projectile, but the 155mm required a very special thin walled projectile to carry a submunition as large as possible in diameter. Part of the R&D problem with this, was that the thin-walled projo body needed the strength to resist the compression of the rotating band being installed and being compressed even more when being forced down the barrel. Various designs were tried, to include the rotating band being installed on the baseplate, which is ejected when the fuze functions and propells the submunitions from the carrier projectile.
Originally painted green, the projectile color code was changed to represent antiarmor submunition, so the projectiles are painted black with yellow lettering and yellow diamonds around the ogive.