Abstract: A multifunction clamp and jack system having a generally C-shaped main body with an elongate threaded rod with a top end configured to receive an open end wrench, a socket of a socket or ratchet wrench, a male square drive member of a ratchet wrench or a non-ratcheting breaker bar, the drive member of an electric or air impact wrench or a removable handle member, the bottom end of the threaded rod configured to receive selected workpiece engaging rotary attachments, the male square drive member of a ratchet wrench or electric or air impact wrench. The main body may be supported in an upright vertical position by front and rear base support members allowing it to be free standing. A plurality of interchangeable workpiece engaging attachments are provided for clamping, holding, or lifting variously shaped workpieces or objects.