SV135 eyepiece is a good assistant for you to observe and take pictures of the planets. More comfortable to view the moon, Jupiter and Saturn. 36°-52° field of view. This is a zoom eyepiece considering that it zooms from 7mm to 21mm. which allows you to see different wide field of view under the same viewing conditions. Meet your different needs. Provide comfortable observation experience. 13-14mm wide eye relief can also provide an easy and pleasant viewing experience. It is also friendly to people wearing glasses. This SVBONY red laser collimator has a 1.25" barrel and comes with a 2" adapter. It is suitable for both 1.25" and 2" Newtonian reflector telescopes. When you upgrade your 1.25" telescope to a 2" telescope, you do not need to buy an additional collimator to calibrate the 2" telescope.