President Rodrigo Duterte has been wearing an AirTamer in his recent public engagements to keep him healthy and protect him from allergens and viruses, Malacañang said Friday.

The explanation came after the 74-year-old President was seen wearing a rectangular device when he welcomed Indian President Ram Nath Kovind at Malacañan Palace on Friday afternoon.

“That is an air purifier, para (so) he will be protected from persons within his proximity who have coughs and colds,” Presidential Spokesperson Salvador Panelo said in a text message.

A pocket air purifier emits a constant stream of healthy negative ions that force airborne pollutants away from one’s personal space to give him a zone of cleaner and healthier air, according to the website airtamer.com.

It was not the first time Duterte wore the AirTamer.

Photos from Malacañang showed that Duterte first used the gadget at the 42nd Cabinet meeting held on October 11.

The President also had the neckpiece on during the 45th Philippine Business Conference and Expo on Thursday, a day before his meeting with Kovind.

He also wore it during a joint command conference with high-ranking police and military officials and a meeting with the Philippine contingent to the 46th Ship for Southeast Asian and Japanese Youth Program on October 15.

The Chief Executive was also seen using it during his meeting with Filipino athletes and the switch-on celebration of the San Buenaventura Power project on October 16.

Critics have raised concerns that Duterte is no longer fit to serve the country due to his health issues.

However, Panelo said on Tuesday that the President is “perfectly healthy.”