Abstract: A portable, hand-held drill, or an attachment therefor, comprising an assembly of parts for generating focused beams of light to be directed alongside the drill bit, whereby the positions of the light spots projected on the work surface serve as indicia of the angle between the drill bit and the work surface. In a preferred embodiment, the light beams are generated 90.degree. apart along the circumference of a circle concentric with the bit, and normal thereto, such that perpendicularity of the bit is indicated by positioning the light spots at equal distances from the bit. It is also preferred to include means for adjusting the beam angle, such that the projections on the work surface can be located at the same distance from the tip of a short drill bit as from the tip of a long bit.