A microscope eyepiece micrometer is ideal for anyone wishing to take a measurement from an object that is being viewed under a microscope. This eyepiece is compatible with our Philip Harris range of stereomicroscopes (WF10X/20mm). To fit simply remove the original eyepiece from your microscope which sometimes involves the loosening of a small screw on the eyepiece tube and replace with the eyepiece containing the micrometer. The eyepieces can be changed back if measurements are no longer required.Suitable for use with the following microscopes:Philip Harris SFX-31 Stereo Microscope - B8R07236Philip Harris SFX-34 Stereo Microscope - B8R07237Philip Harris SFX-51 Stereo Microscope - B8R07238Philip Harris SFX-91 Stereo Microscope - B8R07239Also compatible with these discontinued models:Philip Harris ST-30-2LF StereoPhilip Harris ST-30-2LEDF StereoPhilip Harris ST-40-2L StereoOlder Philip Harris Stereo Microscopes with a removable WF10X20mm eyepiece