An electrically-driven device, the device comprising: a handle; a head, the head comprising: a head base being coupled to the handle and movable in at least two dimensions relative to the handle, and a skin treatment head attachment including brush unit transmission (202, 204) and a brush unit rotatably coupled to the brush unit transmission, a second head attachment including a skin treatment implement constructed to treat skin or a cutting unit constructed to cut hair, wherein each one of the skin treatment head attachment and the second head attachment is releaseably engageable, one at a time, with the head base; a motor, the motor being contained at least partially within the handle; a first transmission coupled to the motor; a first driven shaft coupled to the first transmission, opposite the motor; and a second driven shaft coupled to the first transmission, opposite the motor; wherein the first transmission being constructed to translate rotary motion of the motor to linear, reciprocating motion of the first driven shaft and to the second driven shaft; wherein, when the skin treatment head attachment is releaseably engaged to the head base, the brush unit transmission is coupled to one of the first or second driven shafts and translates the linear, reciprocating motion of the coupled first or second driven shaft to rotary motion, rotating the skin implement. a handle; a head, the head comprising: a head base being coupled to the handle and movable in at least two dimensions relative to the handle, and a skin treatment head attachment including brush unit transmission (202, 204) and a brush unit rotatably coupled to the brush unit transmission, a second head attachment including a skin treatment implement constructed to treat skin or a cutting unit constructed to cut hair, wherein each one of the skin treatment head attachment and the second head attachment is releaseably engageable, one at a time, with the head base; a head base being coupled to the handle and movable in at least two dimensions relative to the handle, and a skin treatment head attachment including brush unit transmission (202, 204) and a brush unit rotatably coupled to the brush unit transmission, a second head attachment including a skin treatment implement constructed to treat skin or a cutting unit constructed to cut hair, wherein each one of the skin treatment head attachment and the second head attachment is releaseably engageable, one at a time, with the head base; a motor, the motor being contained at least partially within the handle; a first transmission coupled to the motor; a first driven shaft coupled to the first transmission, opposite the motor; and a second driven shaft coupled to the first transmission, opposite the motor; wherein the first transmission being constructed to translate rotary motion of the motor to linear, reciprocating motion of the first driven shaft and to the second driven shaft; wherein, when the skin treatment head attachment is releaseably engaged to the head base, the brush unit transmission is coupled to one of the first or second driven shafts and translates the linear, reciprocating motion of the coupled first or second driven shaft to rotary motion, rotating the skin implement.