What is survival suits?

A survival suit is also called an immersion suit (or more accurately an immersion survival suit) is featured of waterproof dry suit that protects the wearer from hypothermia from immersion in cold water, a heavy duty 100% waterproof metal zipper(SZIP Metalproof) is applied to keep the watertight and airtight for the survival persob, after abandoning a sinking or capsized vessel, especially in the open ocean.