Hmm, there are things called metal detectors.

Kraft Foods is recalling about 242,000 cases (about 6,000,0000 boxes) of its macaroni & cheese after eight consumers complained about possible pieces of metal in the well-known blue boxes.

It is possible some boxes may contain small pieces of metal, Northfield-based Kraft said Tuesday. The company said no injuries have been reported and apologized to consumers. Some consumers have found pieces of metal.

It is the latest in a string of recalls by the food company over the past several months.

The company recalled 7.25-ounce size boxes of Kraft original flavor macaroni & cheese with “best when used by” dates of Sept. 18, 2015, through Oct. 11, 2015, with “C2” directly below the date. The “C2” refers to the production line on which the affected products were made.

The products were shipped in the United States and to several other countries, but not Canada.

The cases include single packages, three-pack boxes, four-pack shrink-wrapped packages and five-pack shrink-wrapped packages, the company said.