The first number is magnification: the image appears ten times closer than it does to the naked eye. The second is the diameter of the front lenses in millimetres, which decides how much light the instrument gathers.

Dividing the second by the first gives the exit pupil, in this case 4.25 mm. That figure is what determines how bright the view stays as the light drops at dusk and dawn, which is when most wildlife is worth watching.

10x42 is the configuration that does the most jobs well. Ten times magnification resolves plumage detail and antler shape at distance without the field of view narrowing to the point where you cannot find a moving bird. A 42 mm objective keeps the instrument bright at first and last light while staying light enough to carry all day round your neck.

8x42 is steadier in the hand and easier for a beginner. 10x50 is brighter still but noticeably heavier. We chose the middle, deliberately, and we sell it properly rather than carrying all three badly.

None optically. Same body, same glass, same rangefinder, same warranty. Green is the usual choice for stalking and woodland hides where you would rather not present a hard dark silhouette. Sand disappears against stubble, dune and open hill. Black is the usual choice for general use and travel.

Pick on preference. Nothing about the performance changes.

Yes, and it is the use they get most. BAK4 roof prisms and a 4.25 mm exit pupil are what let you separate a subtle wing bar or an eye ring rather than guessing at a shape.

The rangefinder is an addition, not a compromise. You can ignore it entirely and use the instrument as a straightforward pair of binoculars.

Yes. Ranging and glassing from a single instrument means one thing round your neck instead of two, and one movement instead of two when the light is going.

They are an observation and ranging instrument. They are not a substitute for the judgement that decides whether a shot is safe and appropriate.

They will, though at ten times magnification you will notice hand shake in a seated stadium row more than you would at eight times. Rest your elbows on something and the view settles.

Yes, provided you twist the eyecups down. Spectacle wearers should use the eyecups fully retracted so the eye sits at the correct distance behind the eyepiece. Anyone not wearing glasses should twist them fully up.

If you see a dark ring round the edge of the image, the eyecups are in the wrong position for you. That is the usual cause, not a fault.

Three steps, once, and then you leave them alone:

• Set the hinge width until you see one circular image rather than two.
• Cover the right objective, and focus on a fixed object with the centre wheel using your left eye only.
• Cover the left objective, and bring the same object into focus using the dioptre ring on the right eyepiece only.

From then on, use the centre wheel alone. Note your dioptre setting so you can put it back if somebody else borrows them.

Yes, using a standard binocular tripod adapter fitted to the front of the centre hinge. At ten times magnification a tripod makes a visible difference when you are watching one place for a long time, such as a nest site or a hillside at dusk.

The binoculars, objective and eyepiece covers, a neck strap, a carry case and a cleaning cloth, plus the instruction sheet. The exact contents are listed on the product page.

Harnesses and replacement straps are sold separately in Accessories.

It sends a short infrared laser pulse at whatever is in the aiming reticle and measures the time the reflection takes to return. The distance appears in the display inside the right eyepiece, so you never take your eyes off the subject.

It is a Class 1 eye-safe laser. It is invisible, and it does not disturb wildlife.

The rated maximum is on the product page. In practice the honest answer is that it depends on the target: a hillside, a building or a treeline will return a reading much further out than a single deer standing in wet bracken.

Reflective, large and light-coloured targets read furthest. Small, dark, soft or angled targets read shortest. Every laser rangefinder on the market behaves this way, whatever the headline figure on the box.

Heavy rain, fog, falling snow and shimmer on a hot day all scatter the pulse. Glass in front of the lens will usually return the distance to the glass rather than to what is beyond it, so range through an open window rather than a closed one.

If you get an inconsistent reading, aim at something solid immediately behind or beside your subject and use that instead.

It takes a single CR2 cell, and the unit powers down on its own after a few seconds of inactivity, so ordinary use across a season is undemanding.

If you are going somewhere remote, carry a spare. It is a small, cheap and common cell.

Yes. With the rangefinder switched off, or with a flat battery, they work exactly as ordinary 10x42 binoculars. The optical path is unaffected.

It is a published sealing rating rather than a marketing word. The 6 means dust tight. The 5 means protected against water jets from any direction, which covers driving rain, spray and rinsing the body off when you get home.

What it does not cover is being put under water. These are field instruments, not diving equipment. Keep them out of the water and they will shrug off any British weather you take them into.

Yes. The body is IP65 rated, which covers driving rain and spray from any direction. Wipe the external lenses dry afterwards and let the body air before it goes back in the case.

IP65 does not cover being put under water. Treat them as field equipment, not diving equipment.

No. External condensation forms on any cold glass brought into warm damp air, exactly as it does on a window. It clears on its own. Fogging on the inside of the glass is a different matter: that is a fault, and it is covered by the warranty.

Blow or brush loose grit off first. Dry grit dragged across a coated lens is what causes fine scratches, not the cloth itself.

Then breathe on the glass and wipe gently with the supplied microfibre cloth in a circular motion. Avoid household glass cleaner, alcohol wipes, tissues and shirt cuffs.

Dry, with the covers on, out of a hot car boot and away from a radiator. If they have been out in the rain, let them dry in the open before the case goes shut on them.

Free to UK mainland addresses, tracked, 7 to 10 working days. You get a tracking link by email when the parcel is dispatched.

Full detail is in our Shipping Policy.

Not at present. We sell to consumers at UK addresses only.

You have 30 days from delivery to tell us you are cancelling, and 14 days after that to send the goods back. You may examine and handle them as you would in a shop, which includes taking them outside and looking through them.

Email us with your order number to start it. The detail, including who pays return postage, is in our Refund Policy.

Email us with your order number, a description of the problem and a photograph or short video. We sort it out. Your rights under the Consumer Rights Act 2015 are not affected by anything we say here.

Two years from delivery against defects in materials and workmanship in normal domestic use. That sits on top of your statutory rights rather than replacing them.

Within 24 to 48 hours, excluding weekends and UK bank holidays. Customer service is open Monday to Friday, 9am to 6pm.

The card and wallet options shown at checkout, plus the pay later options listed there. Nothing is charged until you complete the order.

No. We are online only, which is part of why the instrument costs what it does. What we offer instead is published specifications, a full answer to any question before you order, and 30 days to change your mind once it is in your hands.

Bramwell Views is the trading name of AKYT LTD, company number 17022802, registered in England and Wales at 71–75 Shelton Street, Covent Garden, London WC2H 9JQ. We sell to consumers in the UK only.

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