Turkish world-record-holding diver Şahika Ercümen on Wednesday sent President Recep Tayyip Erdoğan and first lady Emine Erdoğan a postcard from an undersea postbox in Sabah, Malaysia.

Ercümen dived to a depth of 20 meters (65 feet) to reach the undersea postbox, located off the coast of Mataking Island in Sabah.

Holder of 11 different diving world records, Ercümen hopes to raise awareness on preserving oceans and their biodiversity. She is also an ambassador of the Zero Waste program, led by Turkey’s first lady.

“We have only one home. In our fight against climate change, we need to protect the world’s lungs, our oceans,” she said.

The Mataking undersea post box was installed in 2006 on the wreck of a wooden ship that has turned into an artificial reef, providing a natural habitat for different sea creatures.