10mm Helical Focuser. 20mm Back Focuser. And the versatile Guide Scope can double as a straight-through finder scope with an optional 1.25" eyepiece installed. For example, insert a 20 mm eyepiece to create a 9.5x50 finder scope, or insert one Illuminated Centering Eyepieces for use as a finder with illuminated crosshairs for easy aiming.
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