Spare / replacement microscope power lead (M-984).To power the following microscopes:Philip Harris M-100FLED Monocular Microscope - B8R05547Philip Harris B-20R Monocular Microscope - B8R05544Optika B-151 Monocular Microscope - B8R05554Optika B-157 Binocular Microscope - B8R05555Optika B-159 Binocular Microscope - B8R05564Optika B-62 Monocular Brightfield Microscope - PP00050385Optika B-66 Binocular Brightfield Microscope - PP00050386Also for use with the following now discontinued microscope models:Optika B-50 Monocular MicroscopeOptika ST-30-2LED Stereo Microscope