LBTEK 30mm Retaining Ring Fixed Stainless Steel Mount is used to mount Optical Components with a 30 mm Diameter, supports Left- and Right-Handed Configurations, and has long-term Alignment Stability advantages compared with standard optical mounts. The Optical Components are fixed by a Retaining Ring, with an M31x0.5 threaded hole, and can be used to mount various optical assemblies. Each mount comes with a Stainless Steel Retaining Ring, and the Retaining Ring can also be purchased separately. The M6×0.25 Precision Adjuster can provide the mount with an Angular Adjustment Range of ±4°, the adjustment mode is horizontal adjustment, and 3-axis Adjusters with Knurled Knobs are optional.