<ul> <li>Front side - T2 female thread</li> <li>Rear side - T2 male thread</li> <li>Added length - 40 mm</li> <li>Weight - 46 g</li> </ul> <p>T2 is M42x0.75 thread. Some lenses and optical accessories have such thread.</p> <p>This extension tube purposed for macro applications to allow shooting from shorter distances.</p> <p> </p>