The contaminants listed are small pieces of metal. There are three specific brands listed by the USDA for recall.
Spare Time Fully Cooked Buffalo Chicken Strips.
You can see the packaging of the specific products effected here.
The products were shipped nation wide, but luckily there have not been any reported incidents from the recalled items.
If you have the products in your freezer, the USDA is advising that you either throw them away or take them to the place you purchased them. The specific brands are listed below directly from the USDA website.