(CNN) - Graco Children's Product is recalling over 3 million child car seats because faulty buckles make it tough to free a child in an emergency.
The National Highway Traffic Safety Administration wants Graco to recall another 1.8 million seats that use the same buckle.
Some say the red release button in the center of the harness can get stuck and be difficult to unlatch.
Graco officials say food and dried liquids can affect the buckle over time.
Customers are being offered "new and improved harness buckles" at no cost.
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