In the largest such child car seat recall in history, Graco is voluntarily recalling 3.7 million car seats over a buckling issue.  The company is contesting a government request to recall an additional 1.8 million seats over a similar issue.  In a statement, Graco said the voluntary recall affects “harness buckles used on all toddler convertible car seats and harnessed booster seats manufactured from 2009 to July 2013.”  Graco fixed the problem on all car seats sold since July 2013.  Graco car seats sell for between $99 and $400, depending on the model.

Food or liquid in the buckle mechanism can make the seat more difficult to buckle over time, or cause the buckle to become stuck in the latched or unlatched position.  The children’s products company added that it was offering a “new and improved replacement harness buckle to affected customers at no cost.” People can obtain one by calling 800-345-4109 or emailing consumerservices@gracobaby.com.

In the meantime, parents may continue using the seat.  “This does not, in any way, affect the performance of the car seat or the effectiveness of the buckle to restrain a child,” the company said.

For more information, read this CNN story.