Sneaking Suit

The Sneaking Suit is a commonly worn type of clothing in the Metal Gear series, used to tightly wrap up the armor to both provide them with protection and increase speed/agility.

The Boss
In 1965, the Boss donned a white prototype of the suit and kept it on throughout Operation: Snake Eater. It did not provide much defense, but made the Boss extremely swift and agile.

Naked Snake/Big Boss
Naked Snake gets a similar sneaking suit when he infiltrates a weapons lab in Groznyj Grad, Tselinoyarsk. It is made of a black bulletproof fiber designed to be resistent to heat, stamina loss, and reduce damage.

Null/Grey Fox
Big Boss, Null, Gene, Cunningham, and Python were dressed in a similar protective fiber (made out of aromatic polyamide) in Portable Ops. It was officially titled the Close Quarters Combat Enhancer Suit.

Solid Snake
During the Shadow Moses and Manhattan incident, Solid Snake always worn a skin-tight sneaking suit made to protect the user from winter conditions, hypothermia, and chemical weaponry. It was overlapped by a bullet-proof thermal vest as well.

Raiden
Raiden also wore a similar sneaking suit called the Skull Suit due to its fitting so tightly onto the user. It provided no means of real protection, however, and was made solely for executing acrobatics and for managing in water.