The Smart Charger for Li-Ion (2nd Gen) accepts variable voltage in the 100-240V range and includes AC adapters for US, Europe, UK and Australia. This charger is compatible with lithium ion battery packs only. The newer Smart Charger for Li-Ion (2nd Gen) is safe for use with Lithium Ion (1st Gen) battery packs but will not provide charge termination feedback via the LED indicator light.