this shell appears correct for the child's comfort when it reaches 5 months, and can only keep his head and starts to recover otherwise little it seems that it is curl up on itself without any really be comfortable. the gearbox is very average, not enough for a newborn, and even six months the head is kept low. Another negative, the straps are adjustable in height, and I find that they do not stick sufficiently to the child even tightened in three months my son came to pass the arms under the shoulder straps and found himself unmaintained (Unintentional he liked to scratch the belly) over the shell is a bit heavy even empty (but I knew that by buying it) therefore suitable for babies with a birth weight and good for short distances by cons very handy when baby begins to awaken when shopping for example