Comfortable low temperature has two marking methods on the sleeping bag, one is to identify an absolute temperature, such as -10 degrees, indicating that the comfortable low temperature of the sleeping bag is -10 degrees; one is to indicate the temperature range, from red to green or blue For example, red starts from 5 degrees, transitions to light green at 0 degrees, and transitions to dark green at -5 degrees. The meaning of this temperature is: 5 degrees warmer, 0 degrees is suitable, and it feels very cold at -5 degrees. The comfortable low temperature of this sleeping bag is 0 degrees. It should be noted that comfortable low temperature is only a relative concept. There are no industry associations for sleeping bag products, no industry standards, no domestic, no foreign countries. Some large brands and research institutes calibrate their products according to laboratory tests and field experience. Comfortable low temperature. This temperature is only for reference, and it varies from person to person and from environment to environment. In general, sleeping bags originating in Europe and the United States are not suitable for Asians on the temperature scale, because Europeans are more resistant to cold than Asians, so we must pay special attention when choosing.