Intended for use with with longer focal ratio telescopes and eyepieces of narrow to moderately wide apparent fields of view
Free light transmission: 22.5 mm lens aperture; Can be used with additional spacers which is available separately to achieve further focal reduction
Mounting threads: 1.25 inch filter thread; 28.5x0.75 MM on both sides: Threads into eyepieces; camera adapters and other accessories with standard 1.25 inch threads; And can be stacked with additional 1.25 inch threaded accessories
Wider 58 Degree Field of View: The Alstar 1.25 Inch 58 Degree 2.5 mm wide angle telescope eyepiece is designed for astronomy enthusiasts; Offering a focal length range of 2.5 mm to 25 mm and a 58 degree wide field of view to capture more celestial details
Standard 1.25 Inch Barrel and Thread: Compatible with any telescope equipped with 1.25 inch focuser and the 1.25 inch female thread can also be connected with 1.25 inch telescope filter or other 1.25 inch telescope accessories; Whether for planetary observation or deepsky exploration this eyepiece delivers sharp and clear images meeting your high standards for stargazing