The RL-H4C construction laser is available in two versions powered by a NiMH rechargeable battery pack or alkaline 'D' cell batteries. The rechargeable version can also be operated with AC power. It offers more than 100 hours of continuous use with alkaline batteries and up to 60 hours on a single charge. The high-power 2.4-mW diode enables a 2,600-ft.-diameter working radius with an accuracy of ±10 arc seconds and a ±5° self-leveling range. The 635nm visible beam allows use for both interior and exterior alignment applications. The unit comes with a slope matching function and IP66 dust/water protection rating.