The 3.7V AC Charge Adapter can conveniently charge your 18650 Lithium-ion batteries in any 110v outlet.  The adapter plugs directly into the headlamp's battery holder for charging.  This adapter fits all HL50-Q, HL55 and HL09 Headlamps and all HL08 Headlamps purchased after June 2014.

This Adapter is NOT compatible with out HL50 7.4V Headlamp.