The Cumulus Junior 300 is a kids' down sleeping bag built for summer camps and warm-weather overnight trips — a 5°C comfort and 3°C limit rating place it in the two-season spring/summer category. The 300 g fill is 850-fill-power goose down (96/4 ratio, RDS-certified) arranged in box baffles inside a lightweight Pertex Quantum shell (15D ripstop, 29 g/m²).
A total weight of just 550 g and a packed volume of 2.8 liters make the Junior 300 practical to carry in a small kid's pack — a warmth-to-weight ratio of 5.5 is a realistic figure for a down bag at this scale. An adjustable drawcord at the foot end shortens the bag by up to 25 cm, letting it grow with the child rather than being outgrown in a season, while the two-way zipper vents on warmer nights and the adjustable, fitted hood with draft tube keeps warmth around the neck. Made in Poland, available in blue or green, sized for children up to 145 cm, and it ships with both a stuff sack and a storage sack.