Ring power and charging

A charging system can include an external power source. The external power source can include a first groove. The external power source also can include a second groove. The second groove can be separate from the first groove. The charging system also can include a housing. The housing can include an internal power source configured to be wirelessly charged by the external power source that is removably coupled to the housing. The housing also can include a component configured to draw energy from the internal power source. Other embodiments are disclosed.