I bought it because I thought the straps of my seat did not fall well in the torso of my baby, this little result with harness, my baby is better protected, the straps are secure in the torso.
Fixing solid air and it's very easy to install. I removed one side of the harness to remove the baby seat. Very easy to use, I recommend. As against the straps of the car seat fit just in the binding. The harness strap is not adjustable.