They are single-use, bomb-pumped x-ray (or higher) laser warheads for missiles. Upon detonation they project multiple laser beams in a 360 degree sphere, and thus may strike multiple targets, some of them multiple times. Since lasers have a narrow, deep damage templates and standard missile warheads a triangular one, they are somewhat better at penetrating the target's armour though far worse at anti-missile fire and useless* in atmosphere.
*Lasers deal 0 damage if the atmospheric pressure is 1.0atm or greater. Half damage in 0.5atm, one-third damage in 0.333atm, etc., always rounding down to whole points of damage.