1. listen:The ear tightens the bottle mouth, hear the inside of the bottle to hum the explanation two layers glass vacuum degree good, heat preservation is good.
2. Look:Whether the bottle mouth is round, not round and easy to leak, heat preservation is not good; Look at the vacuum in the bottom of the bottle and the mouth is in good condition. It can't be damaged.
How to buy air pressure thermos Buy air pressure thermos, except for the insulation effect and the shell quality of the ordinary thermos. The following three points should also be noted:
1. Air pressure is good.Note that the air pressure cap should not be tilted at the bottom of the press. It should be vertical downward and the size should be large. If it is too small, it will affect the effect of water discharge. If you use one hand against the hole and the other hand is pressed against the top cover, there should be no chronic air leakage.
2. Accessories is good .The water pipe is made of stainless steel, the sealing ring of the bottle is made of silica gel, other materials are not strong, or unsanitary.
3. The bottom rotation plate should be able to do 360-degree rotation, and the rotation should not be strenuous.