A device for locating structural stud members beneath a surface such as a shingled roof. The device includes a support block for receiving a probe member, the probe member extending from the support block at a selected arc of curvature terminating at a point spaced apart from the support block. An indicator member is fixed to the support block, the indicator member extending from the support block parallel to the probe member and having an end coextensive with the termination point of the probe member such that the indicator member provides a user with the orientation and termination point of the probe member when the probe member is beneath the surface. In use, a hole created within the surface and the support block rotated on the surface until the probe member abuts an edge of a structural stud member.