DETROIT (AP) — Combi USA is recalling more than 39,000 car seats because they can transmit too much force to a child's chest in a crash.

The recall covers certain Coccoro Convertible Child Restraints with a model number of 8220. They were manufactured from Jan. 1, 2009 to June 29, 2016.

Here is a link to the recall notice. 

Government documents say the problem happens when the seats are installed in a forward-facing position and secured only with a vehicle lap belt.

The problem was discovered in government tests. Combi says in the documents that there is little to no risk in real-world crashes. It has no reports of injuries.

Combi will notify owners and send them a cover for the bottom of the seat that reduces the force on children's chests. Distribution of the covers started on July 11.