Lock if old. Via IGN. http://uk.ign.com/articles/2015/01/14/new-3dsxl-doesnt-include-charger-here-are-some-options
Nintendo responded to our request for comment on why it was decided to leave the charger out of the box. According to Nintendo, it was a measure designed to save costs for consumers who may already own a 3DS or DSi system. According to Nintendo, "New Nintendo 3DS XL uses the same AC adapter as any Nintendo 3DS or Nintendo DSi system. Rather than raise cost of New Nintendo 3DS XL by charging consumers for a component they may already own, we are giving them the option to only buy if they need an AC adapter."