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RIDGID launches AC87004P 18V 4.0 Ah Li-ion battery 2-pack. These 4.0 Ah batteries will provide up to 3x the run time compared to the 1.5 Ah Li-ion battery (AC870015). These 4.0 Ah batteries are 10% smaller and 10% lighter than the previous model (AC840087). As always, these 4.0 Ah batteries are 100% compatible with all RIDGID 18V tools.