Stainless steel lunch boxes have arrived from India and Thailand.
The simple design and timeless visuals mean you can use it for a long time. 
By the way, this stainless steel lunch box is commonly used in India and Thailand.
In India, curry is the staple food, and it is not uncommon to have curry for all three meals.
That's where this stainless steel lunch box comes in handy.
This prevents the smell of spices and colour transfer, and the norm for lunch in India is to pack rice and curry into each layer and eat it on the go.
The bento culture is deeply rooted in India. I feel a sense of affinity with the same bento culture.