We once sold a range of stainless steel vacuum flasks of a well known classic brand, but it transpired that production had been shifted to the far east, and the famously thick walled construction made lighter and thinner for our comfort and convenience. Truth be told though we had always been searching for a proper glass vacuum flask, as stainless steel, for all its sturdy virtues seems unable keep drinks as hot (or as cold) for as long. We then discovered these, silvered glass Dewar flasks from northern Scandinavia. First produced in 1934 they are a legacy product, similar to the Porte Savon, or Milton Brook pestle and mortar, something that helped build the foundations of a company that has since shifted focus to other more lucrative fields but has continued in production none-the-less, perhaps as something they know cannot be improved or surpassed, and to which they are proud to be associated. These are thermos flasks built for the rigours of the arctic winter and promised even in those freezing climes to keep boiling liquids above 50°C for at least 24 hours. And yes they might be breakable, but as my farmer grandfather kept the same flask for over 40 years, I can't help but think his careful handling was more than adequately rewarded by a hot cup of tea, and in case of unfortunate mishaps replacement vacuum vessels are now available. In three sizes, 0.45l, 0.7l, and 1.0l.