The Microclimate Cooling System (MCS) is a self-contained Vapor Cycle System (VCS) which cools and ventilates the MOPP IV NBC protective suit and face mask of the operator of an armored tracked combat engineering vehicle, the M9 earthmover.
Operational mode selection and control is provided by a remote console located within the crew compartment
With over 120 units fielded, the MCS has proven itself for many years and takes second place to no one for dependability and ruggedness.