Alvin 961B Beam Compass<div style="text-align: left;"><strong>[Product Information]</strong><ul><li><span class="a-list-item"> Two 13 inches ungraduated beam bars. </span></li><li><span class="a-list-item"> Spring-loaded thumbwheel on the top of each slide. </span></li><li><span class="a-list-item"> Includes spare leads and needlepoint. </span></li><li><span class="a-list-item"> Packaged in a protective case with clear cover. </span></li><li><span class="a-list-item"> Size: 13 inches </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/31psndPo6dL.jpg" noproxy>