Abstract: A hand-held linear measuring device is enclosed within an elongated housing which has a handle at one end and an opening at the opposite end. A wheel mounted on the housing and protruding through the opening rotates as it engages and is drawn across a surface to be measured. As the wheel is rotated, it rotates a selector disk about a parallel axis. A plurality of radially extending elongated slots are formed in the selector disk at equally spaced azimuthal locations. A contact member extends transversely through each slot and is selectively, releasably, fastened thereto at one of a plurality of predetermined radial positions. As the selector disk rotates, it causes the contact members to successively engage an electrically conductive resilient whisker member extending across the path of their advance.