Ford Motor Co is recalling 661,000 Explorer sport utility vehicles (SUVs) in North America upon the request of U.S. regulators as retention pins could loosen and allow roof rail covers to detach from the vehicle.

Dealers are due to install push-pins and replace any damaged roof rail covers and rail clips. The recall by the second-largest U.S. automaker covers 2016 through 2019 model year cars.

The National Highway Traffic Safety Administration first inquired about the issue in early 2020 following 11 reports of roof rail cover detachment, Ford said in documents posted Sunday.

In April, the administration requested Ford issue a recall, which the carmaker had initially said was not necessary because of the low likelihood of a roof rail detaching, its small weight and the fact drivers would likely detect a loose roof rail cover, according to the documents.

In November, Ford said it would extend its warranty to cover the issue for a ten-year period or 150,000 miles before agreeing to the recall on April 30.

The automaker is not aware of any accidents or injuries associated with this condition, a Ford spokeswoman said on Sunday.

The vehicles covered by the recall have roof rail covers that are painted black, absolute black or silver. Customer notifications are set to begin the week of June 28.

The recall includes 620,483 vehicles in the United States, 36,419 in Canada and 4,260 in Mexico.