Size:0.5x Lower magnification and wider field of view;shorter exposure times for astrophotography when you are using the SVBONY 1.25" 0.5x focal reducerIt can reduce the telescope focal length to the 0.5 to 0.8 times of the original's;it's also great for visual use for a bigger FOV and is indispensable when CCD imagingGreat tool for astrophotography peReduces exposure times and simplifies astrophotography;works great to photograph0.5x focal reducerReduce 0.5-0.8x of the focal length for telescope eyepiece lensDouble the photographic image/video fieldRecord a significantly larger portion of the lunar surface with web cameraStandard 1.25"interfaceFits for any standard 1.25" telescope eyepiece lenFMC optical glass design2 element Optical Design Increases the Light transmittance;the imaging is brighter and clearerCapture wider field of viewThe focal reducer is great for visual use for a bigger FOV and is indispensable when CCD imagingFully threaded to minimize reflectionsBlackened edges and blackened interior to reduce scattering of stray light and maximize contrastFully metal for long time usingBesides the male thread;it also has female thread at the rear end to fit filters etcSpecifications:: Focal reducer: 0 .5xBarrel size: 1.25"/31.7mmThread interface: M28.5x0.6 thread at both endsSleeve material: full metal aluminum alloyLens coated: broadband coatedLens ,aterial: pure optical lensTotal height: 20mmPackage includes:1 x SVBONY 0.5x focal reducer