From Summit Racings site:
These roller rocker arms from COMP Cams are made from high-quality aluminum alloy, anodized for durability and good looks. They have needle-bearing trunnions to allow for high valve spring loads (over 350 lbs.) and a tensile strength of 80,000 psi. While these rockers are more expensive than COMP Cams High Energy or Magnum rockers, they're a great choice for any race application...
-16 means the number of arms in the package.
Check the application, compare their price and make him an offer at 50% of that or less.