NT-01 is a cost-effective portable oxygen concentrator. After actual measurement, the noise of NT-01 is below 58 decibels, which is a quiet and normal environment. This can protect the health of you and your family. Whether it is sleeping at night or in various quiet occasions, the low-noise oxygen generation mode allows you to fully participate in the ongoing activities without worrying about the noise being disturbed by your surroundings.It is the best gift for your family.