These chunky Rototo slipper socks in Gray / Blue / Light Blue are knitted with a machine used for ski sock manufacturing between the 1980s to the early 1990s. As ski socks have become thinner because of the improvements in ski boot technology, the quantity of ski socks made with this machine has been reduced. Currently this specially-designed machine is used to knit socks for fishermen, woodsmen and other workers in the cold areas. This item is made of the same material of those worker’s socks, thick wool/acrylic blend yarn, and features a brushed sole, so it is ideal not just for everyday use, but also for outdoor activities such as fishing and camping.