phage peptide 

Of note, we carry 3 good linear peptide libraries (9-mer, 16-mer, and 20-mer), which are based on the same true phage system as NEB Ph.D. peptide libraries. As validated by QC DNA sequencing, over 97% of randomly picked clones from these two libraries contained dsDNA inserts, with no stop codon, single nucleotide deletion or insertion or non-sense frame-shift mutation detected. Moreover, no Cys encoding codon was identified in the peptide library as designed. We also have another cyclic 9-mer peptide constructed using the same technical route. These random peptide libraries with such great quality and diversity can definitely make excellent tools for peptide agent discovery.
https://www.creative-biolabs.com/premade-phage-display-peptide-libraries.html