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8x21 Super mini monocular. Brand new, boxed with no reserve.

This is a stunning little device, 8x magnification, smooth black rubber armoured, weatherproof and small enough to go everywhere with you, it even comes with a weatherproof mini belt case!

The ruby UV-iR coating to the front lens allows excellent viewing in hazy conditions, and the field of view is a massive 131m at 1000m, or 7.4 degrees. For an explanation of what the numbers mean, please see below.

The Details:
8x Magnification
21mm Objective lens diameter
Fold down rubber eyecup
Anti-Haze, UV-iR front lens coating
Smooth, black rubber armoured
Field of view 131m @ 1000m (7.4 degrees)
Twilight factor 12.9
Size 90mm x 30mm
Boxed New
Includes Case. Strap. Cleaning cloth
Two year manufactureres Warranty
What the numbers mean - 8x21

The 1st number is the magnification, the 2nd is the diameter of the front (objective) lens.
The larger the 1st number, the closer the subject will come, however as you increase power, you will also get less clarity, less width of view and more shake. As a rule, the higher the power, the shorter the time you can comfortably view through the optic. 8x - 10x is perfect for general use. Above 12x most people would need a tripod!
The larger the 2nd number, the brighter the image will be, and the more detail and clarity you will see, however as you increase size, the monocular will become bigger and heavier, and so less portable.
This size, (8x power - 21mm diameter) produces a very compact, convenient optic, with very good general purpose power. 8x is comfortably hand-holdable, with a wide width or 'field' of vision, so subjects can be found easily, and viewed for a long time.