5CM means 5 safety tips + C-shape body + M-position legs (not 5 centimeters thick!)
The British Association of Babywearing Instructors had proposed the T.I.C.K.S. rule for safe babywearing.
TIGHT – slings and carriers should be tight enough to hug your baby close to you as this will be most comfortable for you both. Any slack/loose fabric will allow your baby to slump down in the carrier which can hinder their breathing and pull on your back.
IN VIEW AT ALL TIMES – you should always be able to see your baby’s face by simply glancing down. The fabric of a sling or carrier should not close around them so you have to open it to check on them. In a cradle position, your baby should face upwards not be turned in towards your body.
CLOSE ENOUGH TO KISS – your baby’s head should be as close to your chin as is comfortable. By tipping your head forward you should be able to kiss your baby on the head or forehead.
KEEP CHIN OFF THE CHEST – a baby should never be curled so their chin is forced onto their chest as this can restrict their breathing. Ensure there is always a space of at least a finger width under your baby’s chin.
SUPPORTED BACK – in an upright carry a baby should be held comfortably close to the wearer so their back is supported in its natural position and their tummy and chest are against you. If a sling is too loose they can slump which can partially close their airway. (This can be tested by placing a hand on your baby’s back and pressing gently - they should not uncurl or move closer to you.) A baby in a cradle carry in a pouch or ring sling should be positioned carefully with their bottom in the deepest part so the sling does not fold them in half pressing their chin to their chest.
Retrieved from: http://babyslingsafety.co.uk/ticks.pdf
Spread Squat position theory
When you’re carrying the baby with a sling, the baby’s position should be C-shaped (or J-shaped) looking from the side, knees lifted higher than buttocks. The baby should be in M-position (Jockey position) looking from the back, the baby’s body, buttocks, thighs and knees are all supported.
(Mamaway baby sling carrier designed based on Spread Squat position theory)
According to International Hip Dysplasia Institute, M-position can support babies’ thigh and knee-joint, legs are able to stretch, buttock stabilized, less pressure is endured by hip joint, and it reduces the chances of hip joint dislocation or poor development.
(Photo retrieved from International Hip Dysplasia Institute)
We would like to remind you, no matter what brand you choose to use, ‘safety’ always comes first, besides the T.I.C.K.S. rule, also read the instructions carefully, practice a few times prior. Also, don’t forget to clean regularly to maintain a good hygiene and to give yourself a peace of mind.