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Orion 13031 Basic 1.25-Inch Rack-and-Pinion Telescope Focuser
Precision 125 focuser with a smooth adjusting rack-and-pinion design is ideal upgrade for a low-quality focuser or for home-built telescope projects
Universal fit base made of durable plastic to fit Newtonian reflector telescopes of 4 aperture and larger
Focuser accepts 125 telescope eyepieces
Has 1-1516 of focus travel with a fully racked-in height of 3-14
Dual knurled focus knobs turn smoothly even with gloves on