We cannot recommend this product highly enough.Please watch the video below as a picture really does speak a thousand words and shows exactly what would happen to a child in a 30mph collision if they have slipped their arms out of their car seat harness.http://www.youtube.com/watch?feature=player_embedded&v=H_0BHlTeHgIAt last, there is a simple, safe solution to prevent children from slipping their arms out of their car seat harness. It simply fills in the gap at the side where the child would normally squeeze their hand through and stops the problem occuring. It doesn't interfere with the harness mechanism, it takes just 20 seconds to fit, its simple safe and brilliant.If you have ever driven a car with an escaping child in the back seat you will appreciate just how brilliant this product is, please do tell everyone you know about it, as the consequences of using a car seat without the harness fitted correctly are horrific and something that no family need suffer.Available in two sizes:-15-30 months30 months - 4 years.Crash TestedView video here