Carrying a small optic can add a great deal of enjoyment to many a hike. However, the weight and size of binoculars can be an issue for many. If you can accept the limitations, a monocular may suit. The Leica 8x20 Monovid is probably the best quality small monocular ever made.
Opticron are a UK optics company that produce monoculars, spotting scopes, binoculars and peripheral equipment. The great majority of their products are manufactured in Japan by 'elite optical manufacturers'. Products are good value, high quality and backed up by warranty and good after-sales service. The 8x20 monocular is quite an old product now, but has undergone a minor design revamp. It is an affordable and good choice for the lightweight backpacker.
For those backpackers amongst us that like to carry a small optic for nature watching and the like, there are surprisingly few decent options. The Viking 8x25 ED monocular is a well made instrument with features that belie its reasonable price.
Three Points of the Compass recently made a plea for those venturing into the outdoors to consider carrying and using a lightweight monocular. But what to buy? Just a few minutes browsing Amazon, eBay, AliExpress and the rest of them immediately reveals how much dross there is to choose from. Take your time, read up on the subject and specifications and choose wisely.
Three Points of the Compass only occasionally carries a little monocular on multi-day hikes, but one of these little gadgets almost always accompanies me on a day hike. I tuck it into my packs hip pocket, there to be (fairly) quickly pulled out should I see something of interest. I actually seldom use it, but just occasionally it has really proven its worth.