Model SV48POptical Design RefractorAperture 90mmOptic Coated FMCObjective Lens Doublet air-spaced achromatic designFocal Length 500mmFocal Ratio F/5.5Eyepiece Barrel Diameter 2-inch (w/ 1.25 inch adapter)Focuser 2 inch R&P Double Speed FocuserMillimeter markings on focuser drawtube Yes360-degree rotatable YesDust plug One 1.25" dust plug includedFinder scope Bracket YesMount Type Dovetail PlateDovetail Plate Length 130mmNet Body Weight 2730g / 96.3ozThe front cap size 109mm, thread size: M103.5×1-6h