A cover for a rotary tool allows a non-sterile rotary tool to be used in a sterile field. The cover comprises a flexible enclosure of a sterilizable material and a rotary pass through extending through a wall of the flexible enclosure. A rotary tool within the flexible enclosure is coupled to drive an inner rotatable member on the rotary pass through. The cover prevents the tool (which may not be sterile) from coming into direct contact with anything in a sterile field.
