Bears with telescopes. Stars overhead. The bedtime story without the book.

2.5 TOG. The cold-weather sleep bag. For nurseries that sit between 61 and 68°F overnight — drafty older homes, basement bedrooms, cold-snap winter weeks where the thermostat doesn't keep up.

Material. TENCEL™ Lyocell shell with DuPont™ Sorona insulation. Sorona is the difference between a 2.5 TOG that feels like a wearable blanket and one that feels like a snowsuit. It's a plant-based polymer that traps warmth at a fraction of the loft of polyester batting, so the bag stays soft and pliable on a six-month-old who's already learning to push back against anything too restrictive. The TENCEL™ shell is the same wood-pulp fiber we use across the sleep line — closed-loop production, OEKO-TEX Standard 100 certified, holds up to repeated washing.

The print. Navy and cream with constellations and small bears — calming pattern for a nursery that's also a science museum.

Construction. Sleeveless, which is intentional even at 2.5 TOG — closed arms are how you overheat a winter baby. The warmth is in the body of the bag, not the limbs. 2-way zipper, bottom-opening, with a fabric guard at the top so the zipper doesn't sit against the skin. Hidden seams. Reinforced stitching at the shoulder where the bag carries the most stress.

Why most brands skip this weight. Most premium sleep-sack brands cap out at 1.0 or 1.5 TOG. The reasoning is that "you can always layer a sleeper underneath." That's true up to a point — but doubling a footed sleeper under a 1.5 TOG bag is how parents accidentally push a baby past the safe overheating threshold, especially when the baby is also wrapped in a blanket because the parent is cold. A purpose-built 2.5 TOG is the cleaner answer for a genuinely cold nursery.

Adjacent TOGs in the same print. Room warmed up to 69–75°F? The 1.0 TOG TENCEL™ Sleep Bag in Stargazing Bears is the year-round weight. For warm summer nurseries above 75°F, the 0.5 TOG Muslin Sleep Bag.

Sizing. 0–6M (8–18 lb), 6–18M (18–28 lb), 18–36M (28–38 lb). Always size to weight, not age. Loose shoulders are a safety issue overnight.

Care. Machine wash cold, tumble dry low. Sorona keeps its loft through repeated washing better than polyester batting. Do not bleach. Do not iron printed panels.

Safety & certification. AAP safe-sleep compliant. Tested to CPSC, CPSIA, and ASTM standards. Material certified to OEKO-TEX Standard 100. Loulou Lollipop is a Certified B Corporation.

Common questions

When is a 2.5 TOG sleep sack the right choice?

When the nursery sits between 61 and 68°F overnight — cold-snap winter, drafty older homes, basement bedrooms. Below 61°F you're past sleep-sack territory and into raising the thermostat.

Will a 2.5 TOG be too warm for an average winter nursery?

If your nursery sits at 69–75°F overnight in winter, the 1.0 TOG TENCEL™ is the right weight. The 2.5 TOG is for genuinely cold rooms. Doubling a sleeper under a 1.0 TOG is also a common winter solution — but you can overheat a baby that way faster than with a single 2.5 TOG bag.

What is DuPont™ Sorona insulation?

Sorona is a plant-based polymer fiber DuPont produces from corn-derived feedstock. It traps warmth without bulk, so a 2.5 TOG sleep bag doesn't feel like a winter parka on a six-month-old. It also keeps its loft through wash cycles longer than polyester batting.

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2.5 TOG Sleep Bags

TENCEL™ Baby Sleep Sack 2.5 TOG - Stargazing Bears

TENCEL™ Waffle Baby Sleep Sack 2.5 TOG - Coconut Milk

TENCEL™ Waffle Baby Sleep Sack 2.5 TOG - Peacock

TENCEL™ Baby Sleep Sack 2.5 TOG - Home Sweet Home

TENCEL™ Baby Sleep Sack 2.5 TOG - All Aboard

Sleep Bag 2.5 TOG - Hedgehog Forest