The worry is that there might be metal fragments in the pills. According to federal regulators, they've already found everything from minuscule pieces of metal up to a wire that's one-third of an inch long. Perrigo got concerned when it realized its pill-making equipment was wearing down prematurely. Metal turned up in about 200 of the 70 million pills checked. The acetaminophen comes in 500-milligram caplets and was bottled in various amounts.