1L = 1000ml。

Therefore, 13 liter thermos can hold 26 kilograms of water.

Attention should be paid to the purchase of insulation barrels:

1. Pour boiling water into the thermos cup, twist the cork or lid clockwise for 2-3 minutes, and then touch the outer surface of the cup with your hands. If the cup is obviously warm, it means that the product has lost its vacuum degree and cannot achieve good heat preservation effect. Don't buy it.

2、? After the thermos cup is filled with water, it should not leak.

3、? The heat preservation barrel should have no pungent smell.

A heavier cup (pot) is not necessarily good. The depth of the tank is basically the same as the height of the shell, and the capacity (difference 16- 18MM) is in line with the nominal value. Some poor quality thermos cups will add sand and cement blocks to make up for the missing weight.

5. You should choose a healthy thermos, which won't rust. There are many specifications of stainless steel materials, among which 18/8 means that this stainless steel material contains 18% chromium and 8% nickel. The materials that meet this standard are green products that meet the national food-grade standards, and the products are rust-proof and corrosion-resistant. Ordinary stainless steel cups are pale and dark in color. If it is soaked in salt water with the concentration of 1% for 24' hours, it will produce rust spots, and some elements contained in it will exceed the standard, which will directly endanger people's health. Not suitable for purchase.