Sailors are receiving a new uniform, with more than 1,000 personnel on operations in hot climates already wearing the new clothing.
Known as Rig22, the uniform is part of a 10-year, £78m revamp of Royal Navy clothing and is designed to be cooler and more practical in hot conditions, according to the service.
The rest of the Navy will be issued the uniform by the end of 2023, with the aim that it can withstand life at sea and be more practical and better fitting.
The new uniform is made from flame-resistant Nomex – which is used in the suits of F1 drivers and allows the body to breathe.
Sailors from HMS Montrose, currently deployed in the Gulf, were among the first to test Rig22.
Warrant Officer First Class Simon 'Bagsy' Baker said the new kit feels "light and airy" and "looks smarter" than the old uniform.
"In the hot climate of the Gulf, it performs head and shoulders above PCS (the old working uniform), making any firefighting and emergency duties far more comfortable," he said.
Engineering Technician Robert Forster said that even though he doesn't work in it all the time, he likes the new uniform.
"The lighter material is cooler and easier to maintain," he said. "The uniform is smart and looks very presentable.
"There are issues with sizing that need to be addressed particularly with the shirt being too tight under the arms."
According to the Navy, feedback from 7,000 personnel has been incorporated into the final design.
Georgina Davies, the uniform project leader, said no part of the uniform will be allowed to "stand still for decades without being reviewed".
"We understand just how important having the right kit is," she said.
"The team want to deliver the best uniform that we can and the project is the way we hope to achieve this.
"Uniform is not simple and getting it right is challenging and complex, but we are committed, and we will work hard to ensure that the money is spent where it really matters," she added.
The Navy will also invest a further £40m to replace other elements, such as boots and belts, while a new Gore-Tex foul weather jacket and thermal layer will arrive this autumn.
Watch: The Royal Navy released a video about the new uniform.