The Stokes Field Guide to Bird Songs includes more species, more time per species, and more sounds per species than any other audio guide to Eastern bird songs. In addition, the recordings are accompanied by an informative pdf booklet that gives precise call and song descriptions of the 372 species included. As a special bonus, one MP3 CD is included, containing all the bird sound files with voice narration removed for use on your MP3 device. Informative pdf booklet gives precise call and song descriptions. 4 CDs; approximately 3.5 hours.