This 10x magnifying loupe is great for examining pen parts and nibs. The lens is 10x21mm in size. The sturdy metal construction allows you to use just your fore finger to hold it, which feels like a more natural hand position. Excellent optics allow for a close examination of everything from scratches and cracks to nibs. When done, simply fold the loupe back inside the housing to protect the lens. Comes with plastic carry case.