New Combat Uniform - are being trialled by the officers and crew of the Type 45 Destroyer DARING while on counter-piracy operations in the Gulf.      Sailors are now wearing a specially designed dark blue kit in place of the Royal Navy's traditional light blue outfit known as the Number 4 dress - this is the first new uniform to be worn by sailors on operations for 20 years.   The new kit is designed to be much more versatile and adaptable to the different weather conditions around the globe.    Each sailor has been issued multiple layers including a t-shirt, shirt, thermal fleece and windproof jacket - all in the new darker colour. The trousers have slanted pockets on the legs so it is easier to use them when sitting down.   The whole uniform has been designed to make it easier to get dressed quickly - something that is essential for those on board ships who may have to be woken up in the event of an incident. The boots have zips as well as laces, and the collar can be turned up and fastened instantly with Velcro rather than fiddling with buttons.     The new uniform is being manufactured by a British company as part of a £250,000 contract. Similar trials of the new uniform are due to take place on the Type 23 Frigate WESTMINSTER and the Fleet Submarine TALENT.