The answer is
crystal clear:
think blue, go
green

Each component has its champion, because when it comes to flasks, different tastes and favourite colours are important. These three materials all have qualities that make them the best for non-isothermal flasks: they enable us to make flasks for adults and children that are super light, at a very affordable price. Thanks to them, you can get a flask for a few Euros only. Because aluminium, stainless steel and plastic are easy to mould materials, reducing manufacturing costs.

Where plastic wins against aluminium and stainless steel, it's the transparence: the properties of polymers enable you to see the level through the walls of the flask, and therefore measure and pace use throughout the hike. It is a major argument for plastic, the unloved industrial material!

Where plastic loses, is on the environmental criteria, as this material is unanimously considered bad for the environment.
An unfair judgement for flasks, as it is one of the every day objects that has made plastic durable! What better than the material to get us out of "throwaway" plastics and give up on single-use bottles? The "Plastic problem" requires some nuance, when you look at it closely. Contrary to popular belief, this component can be sustainable, like our fleeces, that have been made from recycled plastic bottles since 2010.

Let's conclude this chapter on plastic. Almost... You should know that even in an aluminium flask, there is plastic! Yes, hidden inside the flask. Indeed, food safety standards forbid manufacturers from placing food in direct contact with aluminium. A polyamide-based "food-safe coating", plastic-based, is applied inside all aluminium flasks that meet these standards. Yes, sometimes we have to use plastic for safety!

So, when you chose a non-isothermal flask, zero-plastics is almost impossible. Unless you choose one of these solutions:

- bring back goatskins. Sorry, but Decathlon does not intend to go down that road

- look for a glass flask. You will find one, since glass flasks exist, for example at our partner-brand Kimjaly, dedicated to yoga, with this sleek bottle. At Quechua, we have decided against that option: glass is too heavy and too fragile for hiking... A glass flask in the mountains is not a great choice..

- get into stainless steel like us, which we now use in some of our nin-isothermal flasks (with one wall) and many isothermal (double-walled) ones.

Shall we move on the isothermal range?