James Hetfield and co and their own All Within My Hands Foundation - which supports "workforce education, the fight against hunger, and other critical local services" - have called on their fans to help them support the NSW Rural Fire Service and Victoria's Country Fire Authority in their heroic efforts to help protect the communities affected by the on-going blazes in New South Wales and Victoria.
The 'Nothing Else Matters' hitmakers said in a statement: "We are totally overwhelmed by the news of the wildfires sweeping through millions of acres across Australia, with major impact in New South Wales and Victoria.
"The resulting destruction and devastating effects on all residents, animals, the environment and the incredible land in Australia is truly heartbreaking.
"Please join us and do whatever you can to assist as we, along with our foundation All Within My Hands, are pledging $750,000 to the NSW Rural Fire Service and to the Country Fire Authority in Victoria to aid in the relief efforts.
"NSW RFS is the world's largest volunteer firefighting organisation and all funds donated during this State of Emergency are directed toward services related to and victims of these particularly destructive Australian bushfires.
"CFA (Country Fire Authority) is a volunteer and community-based fire and emergency services organisation, which helps to protect 3.3 million Victorians, and works together with communities to keep Victorians safe from fire and other emergencies."
The fires have destroyed 2000 homes, 25 people have tragically lost their lives and an estimated one billion animals have been killed.
Metallica follow in the footsteps of the likes of Sir Elton John, Nicole Kidman, Christ Hemsworth and more, who have all pledged their support and donated to the fight against the bushfires.
A benefit concert is set to take place at the ANZ Stadium in Sydney on February 16, with Queen + Adam Lambert tipped to perform.
