The Advanced Precision Kill Weapon System (APKWS) is a kit that equips Hydra 70 unguided rockets with laser guidance and turns them into precision-guided munitions (PGMs). The weapon bridges the gap between the Hydra 70 and AGM-114 Hellfire systems, providing a cheaper way to hit lightly armored targets. The original version never entered service; an upgraded version, the APKWS II, did, and is designated the AGR-19/AGR-20/AGR-21 with numerous variants.