Based of the popular but expensive Docter 8x21 monocular design, these little guys have slightly more magnification than a pair of quality bridge binoculars but otherwise they are totally inferior. They let in a lot less light, are not intrinsically waterproof and they don't allow for stereo vision.
If they aren't as good then why do we sell them? Well, because we love them and because the best binocular is the one that's with you. Small enough to fit in the front pocket of your coveralls these little guys also have remarkable clarity and use the same Porro prism design used on high end binoculars.
These monoculars fit perfectly in the small pocket of a pilot's inflatable lifejacket and are great for duties, like anchor watch during arrival and departure, when a full set of binoculars are not needed but magnified vision might come in handy.