Winter hit us hard this year. The search for a high quality hot water bottle commenced for several months. Somehow, I chanced upon the German company Hugo Frosch. On it's website it is described as "high quality premium thermoplastic, phthalate-free, water bottles. The classic product line is available with grooved surfaces and also half ribbed, named "Hugo". Product lines are also produced according to the British Standard BS 1970:2012."
It is an absolute pleasure to use this odorless, stain free, water bottle.