a retrofitable attachment for easily and quickly converting most conventional wheelchairs into self - propelled , steerable wheelchairs . the invention includes a drive arrangement easily attachable to one of the rear wheels of the wheelchair , an elongated arm unit easily attachable adjacent one of the front casters of the wheelchair , and a connecting member extending between the arm and rear drive arrangement . the elongated arm unit has an outer drive arm portion and an inner steering arm portion , both of which are mounted for pivotal movement together about a first axis to activate the drive arrangement . additionally , the occupant of the wheelchair can twist or rotate the inner steering arm position about a second axis to steer the front caster of the wheelchair . the steering arrangement further includes a unique gearing system that eliminates dead spots in the steering and allows for easy and uniform manipulation of the steering arm and front caster . in use and with a single hand , the occupant of the chair can both propel and steer the wheelchair as desired .