Board book with electronic sound module attached to inside of extended rear cover Board book, with electronic sound module attached to inside back cover Board book with electronic sounds from panel attached to extended back cover Board book with electronic sounds from panel attached to extended back cover. With electronic sounds module attached to extended back cover Board book with electronic sounds from plastic panel attached to extended back cover Board book, with electronic sounds from sound module attached to extended inside back cover. Board book with electronic sounds, on plastic panel attached to extended back cover Book with electronic sounds from panel attached to extended back cover Electronic sound module attached to extended back cover