<ul> <li>Front side - M26x0.75 female thread and M49x0.75 female thread</li> <li>Rear side - M49x0.75 male thread</li> <li>Weight - 20 g</li> </ul> <p>This adapter allows using microscope objectives that have M26x0.75 mount thread (Nikon BD) in front of lenses with M49x0.75 filter thread (for macrophotography purposes).</p> <p>Tolearances are large enough to fit Mitutoyo objectives with M26x36tpi as well.</p> <p>Machined of high quality aluminium alloy.</p>