
FX (Fetal Flex) Swaddle / Warm Weight 2.5 Tog / Grey
SIZING NOTE: Please use the Sizing Guide in the Product Description section below (scroll down) to determine the correct size for your baby.

Meet the 3-IN-1 FX Swaddle. Designed in Australia, it comes built-in with 3-IN-1 arm positions (Arms-In, Arms-Free, and Hands-Out) to accommodate your baby’s changing needs, preferences, and development stage.
The FX (Fetal Flex) Swaddle is the only swaddle that emulates the natural essence of the womb environment by swaddling your baby in the naturally preferred Arms-Free (Fetal Flex) position, while still suppressing the Startle (Moro) reflex.
Similar to the womb environment, the FX Swaddle provides your baby optimum comfort and feeling of security, promotes better development and self-soothing, while minimising spontaneous awakenings – helping your baby sleep better and longer – providing a gentler way to transition your baby from 'womb to world', and from 'swaddle to sleeping bag'.
Features & Benefits Summary
- Patented built-in 3-IN-1 arm positions (Arms-In, Arms-Free, and Hands-Out) to accommodate your baby’s changing needs, preferences, and development stage.
- Patented design emulates the essence of the womb environment by swaddling your baby in the naturally soothing Fetal Flex position. This Innovative design promotes a more restful sleep experience by calming startle reflex, providing a sense of security, reducing overstimulation, and facilitating natural self-soothing.
- The only swaddle that helps babies gain control of their arm movements, aiding in development, and easing the transition out of swaddling.
- Crafted from premium natural fabrics and designed to be snug yet stretchy, this swaddle ensures optimum comfort, breathability, and reduces the risk of overheating.
- The narrowed/tapered waistline design provides gentle pressure on baby’s belly, which can help ease colic and eliminate gas related issues.
- Designed in Australia based on the principles of safe swaddling.
- Designed to allow proper chest wall expansion, allowing baby to breathe freely and minimising the risks associated with tight chest wrapping.
- Hip-healthy bell shaped design allows baby’s hips and legs to flex and move naturally, which helps the hips develop normally.
- Conforms to the Australian safety standard AS/NZS 1249:2014.
- Two-way zipper for easy nappy changes.
- Escape proof zip-up design – a safer alternative to Velcro or traditional swaddles which can unravel and cover your child’s face.
- Super easy to use – simply place baby in the swaddle and zip up, no wrapping required!
- Easy cleaning/care.
Sizing Guide
STEP 1 – Select Base Size
For babies aged 0-12 months, weight is the most reliable factor when selecting a swaddle size. Height is also important, but age is the least accurate, as babies of the same age can differ significantly in size.Use your baby’s current weight and height to select a base size below:
Size |
Weight |
Height |
Approx |
Tiny/Premmie |
2-3.3kg |
44-50cm |
33-39w (Gestational Age) |
Newborn |
3.3-4.8kg |
50-56cm |
0-1m |
Small |
4.8-6.5kg |
56-62cm |
1-3m |
Medium |
6.5-8kg |
62-68cm |
3-6m |
Large |
8-9.3kg |
68-74cm |
6-9m |
- All measurements are approximate and are for guidance only as all babies are different.
STEP 2 – Should You Size Up?
We recommend moving up to the next size if any of the following apply. Otherwise, stick with the base size from Step 1.
- You’re purchasing during colder months and may need to add extra or warmer layers underneath the swaddle, as this require more room for a comfortable fit.
- Your baby’s weight or height is approaching the upper end of the base size range.
- Your baby dislikes feeling restricted and prefers a looser fit.
Baby’s Growth: What to Expect
Here’s a quick guide to typical baby weight and height growth patterns to help you choose the right size - and know when to size up.
Typical weight gain
In the first week, babies may lose up to 10% of their birth weight but usually regain it over the next few weeks. Most babies double their birth weight by 4–6 months and triple it by 12 months.
Average weekly weight gain:
- 0-3 months: 150-200 grams per week
- 3-6 months: 100-150 grams per week
- 6-12 months: 70-90 grams per week
Typical height growth
- 0-6 months: 2.5 cm per month
- 6-12 months: 1.3 cm per month
NOTE:
- These are averages. Every baby grows at their own pace, and growth may not follow a steady pattern. Growth spurts are common and can happen suddenly.
- To avoid unexpected delays in receiving your swaddle, we recommend you choose the Express Shipping option during checkout. For shipping info please visit: https://sleepycompany.com/shipping-returns-warranty
How the Swaddle Should Fit Your Baby
We recommend trying the swaddle on for size before using it for sleep. When the swaddle is properly fitted:
- It should fit snugly across the upper torso to create a hugged feeling, helping to calm the baby and suppress the startle reflex.
- It should be roomy around the hips and legs to allow natural movement and healthy hip development.
- You should be able to fit two fingers comfortably inside the neck opening.
Signs the swaddle may be too tight
These apply to swaddling in general, regardless of brand or style.
- Consistently rapid, shallow breathing (over 60 breaths per minute at rest). While brief spurts of rapid breathing are normal in newborns, constant fast breathing may suggest restricted chest movement or difficulty breathing.
- Nasal flaring, grunting, or chest retractions (when the skin pulls in around the ribs or neck with each breath)
- Blue or pale skin tone, especially around the lips
Signs the swaddle may be too loose or oversized
These apply to swaddling in general, regardless of brand or style.
- Fabric rides up over baby’s face
- Loose fit around the tummy
NOTE: If you need to exchange your item, please refer to our Returns and Exchanges information here: https://sleepycompany.com/shipping-returns-warranty
How many swaddles do I need?
We recommend purchasing at least two FX swaddles per size. Given how babies can be messy — whether from leaking nappies, spit-ups, or sucking on their hands through the fabric — having a spare can make things easier: one to wash, one to wear, and, if possible, an extra as backup.
Tog Rating and Fabric Composition
What is a Tog?
Tog is a measurement of warmth or 'Thermal Resistance' in a fabric; the lower the Tog rating, the cooler the fabric, and the higher the Tog rating, the warmer the fabric.
FX Swaddle Tog Rating and Fabric Composition
The FX Swaddle comes in various warmth ratings to cover all seasons as follows:
Light Weight Bamboo (Super Stretch) 0.2 Tog
The Light Weight Bamboo (Super Stretch) 0.2 Tog FX swaddle is made from a single layer of thin and incredibly stretchy fabric, consisting of 90% bamboo and 10% spandex. This fabric is exceptionally soft and light, with a silky feel. It's perfect for summer use when worn with light clothing or just a nappy underneath, and suitable for autumn and spring when layered with warmer clothing underneath.
This Super Stretch version provides the highest level of freedom of movement among all our swaddles, making it the ideal choice for babies who prefer unrestricted mobility and have a mild startle reflex (not suitable for babies with medium-strong startle reflex).
Light Weight Bamboo 0.2 Tog
The Light Weight Bamboo 0.2 Tog FX swaddle is made from a single layer of thin and stretchy fabric, consisting of 90% bamboo and 10% spandex. This fabric is exceptionally soft and light, with a silky feel. It's perfect for summer use when worn with light clothing or just a nappy underneath, and suitable for autumn and spring when layered with warmer clothing underneath.
Light Weight 0.2 Tog
The Light Weight 0.2 Tog FX swaddle is made from a single layer of thin and stretchy fabric, consisting of 95% cotton and 5% spandex. It's perfect for summer use when worn with light clothing or just a nappy underneath, and suitable for autumn and spring when layered with warmer clothing underneath.
Standard Weight 0.5 Tog
The Standard Weight 0.5 Tog FX swaddle is made from a single layer of stretchy fabric, consisting of 95% cotton and 5% spandex. This fabric is similar to that of a comfortable t-shirt and is suitable for year-round use and daytime naps. You can layer your baby underneath the swaddle based on the room temperature.
Warm Weight 1.5 Tog
The Warm Weight 1.5 Tog FX swaddle is made from a single layer of stretchy cotton fleece fabric, consisting of 95% cotton and 5% spandex. This fabric features a smooth exterior and a plush, fluffy interior, similar to that of a cosy sweatshirt or jumper. It's ideal for autumn and spring when worn with light clothing or just a nappy underneath and can be layered with warmer clothing during winter for added warmth.
Warm Weight 2.5 Tog
The Warm Weight 2.5 Tog FX swaddle is made from a stretchy cotton fleece fabric, consisting of 95% cotton and 5% spandex. This fabric features a smooth exterior and a plush, fluffy interior, similar to that of a cosy sweatshirt or jumper. While the upper body and sleeves feature a single layer of this fabric, the area from below the chest to the bottom, both front and back, is double-layered, providing optimal warmth for winter. You can dress your baby underneath the swaddle with suitable layers, adjusting as needed to accommodate varying cold temperatures.
Dressing Guide
General Dressing Guide
The FX swaddle is designed to be worn over other sleepwear as an additional layer. When dressing your baby for sleep, room temperature is a crucial consideration, but other factors such as humidity levels in your region, the presence of heating or cooling systems in your house, your baby's individual preferences (like being a hot or cold sleeper), and your baby's health condition (such as having a cold, infection, or specific needs) also influence the choice of an appropriate Tog-rated swaddle and how your baby should be dressed underneath.
As a starting point, we recommend dressing your baby in a way similar to how you would dress yourself for the room temperature: comfortably warm, neither too hot nor too cold. Regularly feel your baby's chest, tummy, or back to gauge their temperature; it should be comfortably warm, neither too hot nor too cool to your touch. You can then add or remove layers as needed.
It's normal if your baby’s hands and feet feel cool. This is due to their immature circulatory systems, which can cause a delay in blood movement to the extremities.
If your baby is sweating or has a red face, consider removing some clothing. This is especially important if your baby is unwell, in which case you should seek medical attention
- This dressing guide is for general guidance only as all babies are different.
Ideal Room Temperature
Maintaining a comfortable room temperature is crucial for your baby's well-being. High room temperatures can lead to overheating, while inhaling cold air may heighten the risk of respiratory illnesses. Babies may also wake up if they are too hot or too cold. Regardless of the weather conditions outside, aim to keep the nursery temperature between 18 and 22 degrees Celsius (64 to 72 degrees Fahrenheit) whenever possible.
Warm Weather Tips
During hot summer days, it may be sufficient to dress your baby in just the FX swaddle and a nappy.
Additionally, consider undoing the bottom zipper of the swaddle so that it is partially open from below the chest to the feet, keeping your baby cooler and more comfortable.
Furthermore, using a fan in the baby's room significantly improves air circulation, creating a cooler atmosphere in warm weather and increasing safety.
Safe Swaddling Tips
- Always sleep baby on the back, not on the tummy or side.
- Do not use swaddle if head can pass through the neck-hole or if neck-hole is too tight.
- It is essential to discontinue swaddling (STAGE 1) as soon as the baby starts showing signs that they can begin to roll, typically occurring between 4-6 months but potentially sooner for some babies. At this point, we recommend transitioning to our 2-IN-1 Swaddle Transition Sleep Bag (STAGE 2), which is specifically designed for rolling babies. For more information, please visit our product page https://sleepycompany.com/shop/transitionsleepbags
- Always follow safe sleep recommendations from children's health care professionals.
Other Info
Fire hazard labelling as per AS/NZS 1249:2014
WARNING - HIGH FIRE DANGER KEEP AWAY FROM HEAT AND FLAME
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Shipping cost and delivery timeframe
Items are posted out from our warehouse in Brisbane Australia. We offer Australia wide and International shipping.More info at https://sleepycompany.com/shipping-returns-warranty/