4 Season Ultimate Sleep Bag – Universal Size

The award‑winning Woolino 4 Season Ultimate Sleep Bag keeps your baby or toddler at the perfect temperature year‑round. Made with breathable merino wool and organic cotton, it fits 2–24 months so you only need one sleep bag for all seasons.

Description:

Say goodbye to guessing which weight sleep sack to use. The Woolino 4 Season Ultimate Sleep Bag uses super‑fine merino wool lining to naturally regulate your baby’s body temperature — keeping them warm in winter and cool in summer. The soft, hypoallergenic fabric helps your little one sleep comfortably all night, and the universal size (2 months to 2 years) means it grows with them, saving you from buying multiple sizes.

Thoughtfully designed for parents, it features a two‑way zipper for quick nighttime changes, shoulder snaps for easy dressing, and a closable seatbelt slot for use in strollers or car seats. A safer alternative to loose blankets, the Woolino Sleep Bag keeps your child covered and promotes back sleeping, while reducing the need for frequent washing thanks to merino wool’s naturally self‑cleaning properties.

Features:

• Year‑round use – Suitable for room temperatures 63–75°F (17–24°C)
• 100% natural materials – Silky‑soft hypoallergenic merino wool lining, organic cotton outer
• Universal size – Fits babies 2–24 months (10–32 lb / 23–35″ tall)
• Temperature regulation – Merino wool keeps baby warm in winter and cool in summer
• Adjustable fit – Underarm snaps for smaller babies
• Travel‑friendly – Closable seatbelt opening for stroller, car seat, or bouncer use
• Easy changes – Double shoulder snaps and two‑way side zipper open flat for dressing
• Quick diaper access – Bottom‑only zip for nighttime changes
• Safe sleep design – Replaces loose blankets and encourages back sleeping
• Durable details – Zipper guards protect baby’s skin and discourage chewing

Specifications:

• Universal Size: 2 – 24 Months; Suitable from 10 – 32 lbs and 23-35″ tall
• Lining Fabric: 100% natural silky-soft hypoallergenic merino wool
• Outer Fabric: Organic cotton

Care Instructions:

• Machine wash on Low, 100°F /40°C max. Close zipper
• Use wool approved or mild detergent
• Do not soak or bleach. Avoid fabric conditioners and softeners
• Hand wash: Gently soak and squish in lukewarm water. Do not agitate, wring, or rub wool against wool
• Tumble dry on “No Heat” setting. Dry flat when possible
• Merino wool by nature is self-cleaning and does NOT need to be washed as frequently as other fabrics. To refresh and reduce washing, air the garment often.

Additional Information:

• What is the TOG rating? Are they winter or summer weight?

  • Woolino 4 Season baby sleeping bags are designed to be worn year-round. They are made from 100% natural breathable fibres and contain NO synthetic filling. Therefore, they do not have a fixed TOG. The fine merino wool lining helps naturally in regulating baby’s body temperature, keeping baby warm in winter and cool in summer.
  • Woolino sleep bags are recommended to be used in room temperatures 63-77F (17-25C). Simply adjust the layers of sleepwear worn under the sleeping bag to suit the nursery temperature. You can find our suggested dressing guidelines on the back of the room thermometer that comes with every baby sleep bag.
• What is the difference between Woolino Ultimate (universal size) and Woolino Basic Baby Sleep Bags?

  • Both collections have the same weight fabrics, merino wool lining and organic cotton outer. The differences are:
  • Woolino 4 Season Ultimate Baby Sleep Bag has universal sizing: 2 months – 2 years, underarm snaps for adjusting the size of the armholes, travel slots for use in car seats, strollers, bouncers etc., & both shoulder snaps.
  • Woolino 4 Season Basic Sleep Bag has a simpler design: no snaps and no travel slots; it comes in traditional sizes: 0-6, 6-18, 18-36 months.