Welcome to our store！</br>1、Dimensions: The internal diameter of this adapter ring is 50mm / 2in, outer diameter is 80mm / 3.1in and the working diameter is 76mm / 3in. 2、Application: Microscope camera adapter ring is suitable for 120X 180X 300X monocular C mount lens with working diameter of 50mm. 3、Main Function: If you have a stereo microscope, this lens ring adapter can help to turn your stereo microscope to video microscope. 4、Aluminum Alloy Material: Lens ring adapter is made of high strength aluminum alloy, with good durability and stability, not easy to rust and deform. 5、Long Lasting: Exquisite workmanship, microscope monocular lens ring adapter has stable and reliable performance, with long service life. <p class="wang-edit-text"><p class="wang-edit-text"> Item Type:&nbsp;Microscope&nbsp;Ring&nbsp;Adapter Material: Aluminum Alloy Internal Diameter: Approx. 50mm / 2in Outer Diameter: Approx. 80mm / 3.1in Working Diameter: Approx. 76mm / 3in <style> .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }</style> 1 x Microscope&nbsp;Ring&nbsp;Adapter1 x Hex Wrench Satisfaction - Our customers are our top priority. If you find any product problems after receiving the goods, such as damage and incorrect quantity of goods, please contact the seller immediately. We try our best to provide you with satisfactoryaftersalesservice</br>