I purchased the ATS 50-400 and am very impressed with the scope. It has an eye relief focus along with a front focus, internal and external batteries for like 10 hours of run time, up to 15x magnification, 3 position screen in screen, record manual and shot capture if you forget to hit the record button, several palates. It was super easy to sight in and is great clarity. The app is also easy to use. Great value that doesn't break the bank !