A protective sheath for tools to prevent marring of finished surfaces when the tool is being used. The sheath is integrally formed as a one-piece elastomeric body that is applied to the exterior surface of the tool, with at least one end of the sheath projecting slightly beyond an end of the tool. In one embodiment the sheath projects at both ends beyond the ends of the tool. One of the projecting ends functions to contact the finished surface and prevent contact between the tool and finished surface, and the other projecting end functions to span the coupling between the tool and another tool. The elastomeric body is freely rotatable relative to the tool and fixed axially relative thereto, and provides a non-rotating surface that may be grasped by a user to support and guide the tool. Annular ribs on the inner surface of the sheath and/or a lubricant incorporated in the material of the sheath provide a reduction in friction, enabling the sheath to rotate freely on the tool even when it is grasped tightly by a person to support and guide the tool.