With a 25mm focal length, this SVBONY 1.25 inche telescope eyepiece provides moderate magnification suitable for various celestial objects, including star clusters, the Moon, and planets. Suitable for broad field lunar observations. 0 degree telecope eyepiece can provide enough detail for bright celestial bodies (such as the moon and planets) to focus on the details without introducing too much distortion. Suitable for beginners to find the moon, stars and other observation targets. 2X barlow lens adopts 2 element one group broadband green film multi coated optical glass; the housing is blackened to maximize image contrast; both that make image more crisp and sharp without additional chromatic aberration. The SV221 diagonal mirror has M28.5x0.6mm thread, standard thread size, you can install 1.25 inch filter. The SV221 main mirror shell is made of precision molded ABS plastic, and the lens barrels at both ends are precision machined from aluminum, which will not be easily damaged.