this is one of the nifty klean kanteens (this one branded with the greenfeet.com logo to show everyone how green you are) -- are by far the best bottles out there; this bottle is slim, cool (temperature-wise as well as trend-wise), and the best choice for a reusable water bottle. other brands are also made of stainless steel but their tops sometimes do not fit, annoyingly "whistle" or are too wide to hold comfortably. (especially for people with shallwesay smaller hands). say. no. more. perfect, and not too expensive, either.