Sub Zero have squeezed a lot into what is a fairly basic piece of kit with the Factor 1 Plus Unisex Bloo John, although one obvious thing that's missing (if you're a bloke) is a fly, but we can live without that.
Plenty of thought has gone into the design of these New Zealand merino long johns, with stuff like flat ankle seams to reduce boot pressure, stretch rib zones for muscle support down the sides, waist and ankles and waffle zones for enhanced heat retention, all of which only become readily apparent once you're wearing the Bloo John.
Other useful features include a low profile integrated elasticised waist for better comfort and high-rise back to keep your kidneys warm.
Being merino you get good wicking and quick drying, and you'll also notice how very soft the Bloo Johns feel, which is exactly what you want with something that going to be next to your skin all day.
The garment also has built-in stretch along both the length and width, which along with all the other design features means that you hardly know you're wearing the Bloo Johns other than they do a fine job of keeping your legs warm - as you'll notice if you're not wearing them.