The comfort of real bedding in the great outdoors
The Naturehike P400 cotton sleeping bag is aimed at those who struggle to get used to the slippery and cold feel of technical nylon materials. Designed for nights in a camper van, caravan, or during stationary camping, this model replicates the feeling of a real household duvet while ensuring reliable thermal insulation down to 1°C.
Textile softness and even heat distribution
The secret of this comfortable sleeping bag lies in its washed cotton inner lining. This breathable textile, which is extremely soft against the skin, allows for a pleasant and gradual diffusion of your body heat, preventing thermal shock when you slip into bed. The thick synthetic filling is forgiving in damp environments. It is a heavy piece of equipment (1.85 kg), fully embracing its focus on comfort at the expense of portability.
Pongee outer fabric: a technical foundation beneath the softness
The pongee fabric used on the exterior combines a tight weave structure with a soft feel, creating the "quilted" sensation sought after in this camping sleeping bag. This textile base differs from the classic technical nylons used for trekking-oriented bags.
Synthetic insulation: moisture tolerance in static use
The synthetic fill retains its insulating volume even in prolonged damp conditions, a relevant point for this warm sleeping bag used in converted vans or stationary camping where ventilation is sometimes limited.
For static campers facing harsher nights (-5°C) and requiring a mummy cut with a hood to completely block cold air drafts while maintaining synthetic insulation, the Naturehike MJ600 will logically take over.
Doubt about which bag is right for you?
The field guide helps you choose based on skill level, temperature, needs, and weight. Support answers specific questions.
Find my bag Contact supportFrequently Asked Questions
The Naturehike P400 has a comfort temperature of 1°C and a lower limit temperature of -4°C, measured to the ISO 23537 / GB/T 38426-2019 standard. These values apply under standard conditions: sleeper in thermal base layers, on an insulated sleeping mat. It is designed for hiking, bivouacking, camping, vanlife use (3 seasons).
The Naturehike P400 is filled with cotton. Cotton is breathable and comfortable for static camping and summer nights, but unsuited to multi-day wild camping because of its weight and bulk. The Naturehike P400 weighs 1850 g, which places it in the standard category.
The lower limit temperature is the lowest temperature at which a reference man can maintain his body heat curled up, according to EN 13537 / ISO 23537-1. It does not correspond to comfortable use: below the limit temperature, the sleeper is likely to suffer from the cold. For real use, the comfort temperature is the main reference.
The minimum recommended temperature is the bag's comfort temperature, measured to EN 13537 / ISO 23537-1. For a 0°C bag, this means a standard sleeper can spend a night without feeling cold at 0°C, provided they use an insulated sleeping mat (minimum R-value of 2 to 3) and wear thermal base layers.
For extreme cold (below -10°C), the most suitable bags combine high-loft down (700 cuin minimum, ideally 800 cuin and above) with a mummy cut that limits heat loss. A sleeping mat with an R-value of at least 4 is essential alongside. For nights between 0°C and -5°C, a good-quality 3-season bag with a 0°C comfort rating is generally sufficient.