Can the B2 work in both 110-120v and 220-240v areas?

Absolutely! The B2 can be used in either 110-120v or 220-240v areas without flipping any switches, modding your B2, or using a power converter. If you're moving to an area with a different plug type than what came standard with your B2, we wouldn't recommend using an adapter and would suggest trying to find another AC cord for your B2 that have the correct plugs.  The B2 uses a non-polarized 2-pin IEC 320 C7 power cord, so you should be able to find one locally with the correct plug for your area.