Abstract: A shield unit which is removably attachable to a machine tool having a cutting member. A rigid transparent sheet is attached to an elongate stem. Also attached to the elongate stem is a clamp. The clamp is adapted to be removably attached to a portion of the machine tool. With the clamp attached to a portion of the machine tool, the transparent sheet is positioned adjacent a cutting member of the machine tool to protect the operator of the machine tool. Preferably, the machine tool is provided with a threaded rod such as a spindle adjustment rod, and the clamp has a threaded portion which threadedly engages the threaded rod to secure the position of the clamp with respect to the threaded rod and to secure the position of the transparent sheet with respect to the cutting member.