We present a new set of zero metallicity models in the range 13-80 M _ { \odot } together to the associated explosive nucleosynthesis .
These models are fully homogeneous with the solar metallicity set we published in Limongi & Chieffi ( 2006 ) and will be freely available at the web site http : //www.iasf-roma.inaf.it./orfeo/public_html .
A comparison between these yields and an average star that represents the average behavior of most of the very metal poor stars in the range -5.0 < [ Fe / H ] < -2.5 confirms previous findings that only a fraction of the elemental [ X/Fe ] may be fitted by the ejecta of \it standard core collapse supernovae .