Baby Muslin Sleep Bag 0.5 TOG in Tanboocel® Bamboo Viscose - Tiny Engineers

Air moves through this weave — hold it to the light and you can see why a warm sleeper stays dry in it.

Cranes, dump trucks, excavators — and the animal operators running them.

This is the lightest sleep bag we make, rated for nursery temperatures between 24 and 27°C — summer nights, top-floor bedrooms, and the many Canadian homes that were never built with central air. When a 1.0 TOG starts to feel like too much, this is the one you reach for.

Material. Tanboocel® Bamboo Viscose, blended with cotton and woven into open-weave muslin. Tanboocel® is a branded bamboo viscose made through a closed-loop process — third-party verified, with a lower water and chemical footprint than the generic bamboo rayon most brands quietly label "bamboo." It gets softer after the fifth wash than on day one, the opposite of how cotton ages.

The print. Light blue ground with construction vehicles (cranes, dump trucks, excavators) operated by elephants, dinosaurs, and cats, with traffic cones, warning signs, and dirt piles.

Construction. Sleeveless on purpose, so your baby sheds heat instead of trapping it. A two-way zipper runs the length of the bag, so a midnight diaper change takes seconds and wakes nobody. The neck and arm openings are bound in soft fabric, not scratchy serged edges, and cut snug — the part that matters most for safe sleep.

Why 0.5 TOG matters. Most premium brands skip this weight; their lightest options start at 0.6 or 0.7 TOG and run warmer than the label suggests. That leaves warm nurseries choosing between a blanket, which the Canadian Paediatric Society advises against, or no sleep sack at all. A true 0.5 TOG muslin solves both.

Need a warmer weight? The matching 1.0 TOG TENCEL™ Sleep Bag in Tiny Engineers is built for the everyday 21–24°C nursery. The 2.5 TOG winter weight picks up below 20°C.

Sizing. 0–6M (fits 3.6–8.2 kg / 8–18 lb), 6–18M (fits 8.2–12.7 kg / 18–28 lb), 18–36M (fits 12.7–17.2 kg / 28–38 lb). Always size to current weight, not age. A neck opening that's too wide can ride up over your baby's face during the night, which is why a snug fit there matters.

Care. Machine wash cold and tumble dry low. Tanboocel® takes the dryer better than bamboo rayon, with less pilling and shrinkage over time. Don't bleach; iron on low only if you need to.

Safety & certification. Tested to Health Canada's Textile Flammability Regulations, and to CPSIA and ASTM standards. The material is certified to OEKO-TEX Standard 100, and Loulou Lollipop is a Certified B Corporation.

Browse all baby sleep sacks.

Free shipping across Canada over $100. Loulou Lollipop is Canadian owned and designed in Vancouver. Free 30-day returns on unworn items in original packaging.

Part of the Big Dreams Sleep System. Sleepers and sleep bags in Tiny Engineers are built to layer together through the night — same print, one system. Complete the set with the TENCEL™ 1.0 TOG Sleep Bag and TENCEL™ Sleeper.