The Olympia Tools(r) X20S(tm) Battery 20V 2.0Ah Li-ion. The Olympia Tools(r) X20S(tm) Li-ion Battery has a digital charge level indicator with minimal self-discharge. X20S(tm) batteries and chargers are 100% compatible with all tools in the X20S(tm) 20V range. Specification: Charge Time with X20S(tm) Fast Charger: 2.0Ah = 1 hour, 4.0Ah = 2 hours.
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