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Gosky Sports BAK4 Binoculars – Review

Last Updated: 29.11.21


Main technical features

The 10x magnification power provided by the optics of this model is accompanied by a relatively full field of view, of 307 feet at 1000 yards. The 42 millimeters multi-layered, green film objective lenses are teamed with 18 millimeters, blue film eyepieces.

This roof prism model is compact and offers excellent image. In the outer shell, you will find a unique mount which allows you to attach it to a tripod. Regarding size, it measures 5.51 by 6.30 by 2.17 inches and weighs about 24 ounces. The exit pupil diameter is 5 millimeters in size, and the exit pupil distance is measures 12 millimeters.


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In-depth information


This great small binocular has excellent value for the money thanks to the many built-in features, the accessories delivered in the package, and its modern design that was perfected with the help of modern and advanced technologies.

At a 10x magnification power, you are delivered with enough zoom for a sporting event or a concert. The BaK-4 prisms with a compact roof design work together with the 42-millimeter objectives and the eyepieces, providing brighter, more precise and better images.

It increases contrasts facilitating use in low-light conditions, circumstances in which it can still deliver quite detailed pictures.

Both the objectives and eyepieces are coated; the latter has a blue film coating, while the first has multiple layers and a green film. This technology is useful for observing true-to-life details at longer distances, without causing eye fatigue.

With a 307 feet field of view measured at 1000 yards, the observing area is also quite large so that you can keep track of a rapidly moving target, just as with reliable birding binoculars.

Another convenient feature this model is known for is the Gosky smartphone mount, one of their latest and newest inventions which help you attach the item to a mobile phone.

Compatible with most modern mobile operating systems such as Android and iOS, it converts your gadget into a long-range camera. This feature eliminates the need for buying an expensive camera lens for this purpose. The adaptor is easy to use and does not require any adjustments to the eyepieces.

Designed to be as versatile as possible, this multi-purpose product can be used for animal watching, sports, concerts and other activities. To answer the needs of all customers, it can be used with or without glasses.

It has adjustable twist-up and down eyecups for comfortable viewing with or without eyeglasses.

Coming together with useful accessories such as a carrying bag, covers for the objectives and eyepieces and a cleaning cloth, the package is complete and eliminates the need of buying other things to fit your binocular with.

Known issues


When used many times and for more extended periods of time, the binoculars can sometimes come apart – this is because one of the screws keeping the joints together can be untightened, resulting in the mentioned problem.

It can be solved at home provided you have a matching screwdriver, but customers considered it annoying.

Another minor disadvantage is that at long distances the clarity decreases and it is harder to focus, but this issue does not affect their intended purpose as sports or concert binoculars.


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Ioana Moldovan

Ioana’s professional experience in the optics field has helped her understand the value of passing her knowledge forward. Her curious personality helps her gather useful information for her readers and her goal is to make technical information fun and accessible to everyone.

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