Feature 1Application: This adjustable focal length mount is suitable for objective lens sizes of 50mm, attachment pillar sizes of 22mm, and center distance of 135mm. 2Stable Structure: Made of high strength alloy material, black appearance, the bracket has stable structure, ensure stable and clear image effect. 3High Performance: Easy to attach, convenient to use, the adjustable focus stand can be precisely adjusted to ensure bright and clear image. 4Application: Perfect microscope accessories, exquisite workmanship, can be widely used in microscope, with good durability and stability. 5Fine Workmanship: Professional manufactured, exquisite workmanship with unique design, ensure stable performance and high reliability.Item Type:AdjustableFocusStandMaterial: Metal alloyApplicable Objectives Lens: Approx. 50mm/1.97inApplicable Connection Pillar: Approx. 22mm/0.87inCenter Distance: Approx. 135mm/5.31in .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; }Package List1 x AdjustableFocusStand