Used Astro-Tech 2" Newtonian Coma Corrector

Condition: This is a used Astro-Tech 2" newtonian coma corrector in excellent condition. The optics and the body are both clean and free of any marks. This includes the original box.    Description: Product Details 2" Coma Corrector for fast Newtonian Telescopes 3-piece modular design (i) Optics in 2" nosepiece with 48mm male filter thread (ii) 2" eyepiece barrel that attaches to optical nosepiece, and (iii) M48 - T2 adapter ring Design optimized for use at f/4.5 but will work well from f/3 - f/6 Reduce coma and field curvature Designed for visual and photographic use Magnification factor of only 1.1x Fully multicoated optics (4 elements / 2 lens groups) with a clear aperture of 43.9mm / 1.73" 2" nosepiece features smooth barrel and is threaded to accept standard 2" filters 2" eyepiece barrel features brass compression ring and dual large thumbscrews Back-focus spacing requirement is 75mm with a tolerance of +/- 5mm. For visual use, connect the 2" eyepiece barrel to the main optica