I will first put forward my different opinions on the answers of several other netizens, for reference only.
First, it is not recommended to buy world-famous brands such as Swiss Sigg or Spanish Laken. Such world-famous brands are very expensive, usually costing around 150 to 300 each. Moreover, they are all made of aluminum. Every time they hit a pothole, it is easy to say that it is cheap. But this 200-piece kettle has a bump and a pothole. It is really heartbreaking.
Secondly, another point that is not recommended for buying aluminum kettles is that because the material is relatively soft, aluminum kettles cannot be made into double layers. Unlike stainless steel, aluminum kettles can be made into double layers for insulation. In addition to thermal insulation, the double-layered kettle also has the advantage that it does not scald your hands when holding hot water, and the water poured into it does not get cold easily in winter (single-layered kettles conduct heat quickly and may freeze and explode in cold weather).
If you don’t pursue the brand, you can go to large wholesale markets and have a look. Many domestic stainless steel sports bottles are of good quality. I bought a Kengbeng and used it for several years. Paint, there are no pits on the surface, and the thermal insulation performance has not been reduced. When I bought it, it was made in China and cost 35 yuan. It was very useful. If you think it is cheap, you can look at the products of famous domestic brands such as Fuguang that produce stainless steel containers.
Another point is that stainless steel water bottles will be heavier when filled with water. Generally, plastic water bottle cages may not be able to bear it. It is recommended to replace them with aluminum alloy water bottle cages. I've seen people lose their water bottles because the water bottle cage was not strong, and the bottle cage broke off in a sharp turn and the water bottle flew out... If you are in the wild, losing the water bottle is very troublesome. After all, water is the source of life.