Little Builder Children's Board Book Sets with Toys are under recall.
The Consumer Product Safety Commission says the cylinder on the concrete mixer and tailgate on the dump truck can detach.
That poses a choking hazard for children.
The sets were sold at stores like Wal-Mart and Christmas Tree Shops.
They were also through Internet retailers like Amazon.com and Barnes and Noble from August 2007 to February 2008.
The code number is ISBN 1-49373-215-9.
Return the sets for a refund or exchange.
For more information contact Dalmatian Press.