What kind of towel rack is suitable for putting in the bathroom?

Update:02 Apr 2021
Summary:

Towel racks are roughly made of the following materials […]

Towel racks are roughly made of the following materials: copper, stainless steel, zinc alloy and aluminum. Generally, the outer layer of the towel rack made of copper, zinc alloy and aluminum should be electroplated. The electroplating effect is good, the use is cherished, and it is also very practical. However, many electroplating manufacturers cut corners on the electroplating layer. Either the electroplating process is missing or the electroplated layer is very thin. In this case, it is easy to fall off.
Towel racks made of copper are more expensive than stainless steel, but they still need to be electroplated. If they are not well protected, green rust will occur, causing unsightly appearance.
If you can still use a stainless steel towel rack, there will be no surface peeling, and it is environmentally friendly, and it is very easy to clean (be sure to clean it regularly). This can achieve the effect once and for all. The price is cheaper than copper, and more expensive than zinc alloy and aluminum.
The solid stainless steel towel rail is the most practical.
Material comparison:
Hollow stainless steel: low-grade stainless steel will rust, the higher the chromium content of stainless steel, the less likely to rust.
Solid stainless steel: Stainless steel contains 16% chromium, has good stability, and has strong corrosion resistance. It will not rust even if it is placed in a humid environment for a long time.
Alumina: The surface is easily corroded and easily oxidized. Easy to flatten or bend,
Zinc alloy: Zinc alloy towel rack will not rust. But the quality is not as good as other materials, and it is easy to break.