Swiss Guard don 3D-printed plastic helmets

The Vatican's Swiss Guard have swapped their ancient metal helmets for ones made by 3D printer.

The papal protection force donned their new, thermoplastic helmets on Tuesday, the unit's 513th birthday.

Unveiled last year, they are designed to be lighter, cheaper and cooler to wear.

The helmets are nearly identical in appearance to the older version, but bear the coat of arms of Pope Julius II who founded the unit in 1509.

According to news site Swiss Info, the Swiss-made helmets are 3D printed from the scan of a 16-century original.

They are expected be used only for ceremonial occasions.

"We have to move with the times," Guard commander Christoph Graf told Catholic news agency KNA last year.

Each helmet weighs just 570g (1.25lb), compared with their 2kg (4.4lb) metal predecessors.

They cost between 900-1,000 Swiss francs ($911-1,012), around half the price of the older version.

Supported by private donations, the Vatican rolled out 98 helmets on Tuesday with 22 more expected for delivery this year.

The 110 member Swiss Guard are responsible for the personal security of the Pope.

They have served the papacy for five centuries, first coming to Rome to protect Pope Julius II in 1506.

Members of the Guard must be Swiss, Catholic, single and under the age of 30. They are also required to complete basic training with the Swiss army.