Just for reference and for Google search keywords: The O.D. MOPP suit is known as a Chemical Protective Overgarment (CPO), and the Woodland camo one is a Battledress Overgarment (BDO). The tape around the arms and legs is M-9 Paper, a sticky-backed chemical detection paper used to detect contamination by liquid (only) agents. The 3 Soldiers are depicted in MOPP (Mission Oriented Protective Posture) Level One. In that level, the suit is worn open or closed, and the gloves, mask, and boots are carried. At MOPP Zero, the mask is carried and suit is readily available, MOPP 2 means you add the boots, MOPP 3 the mask, and MOPP 4 the gloves... At MOPP 4, the suit must be closed up. There's another posture, that of "Mask Only" that will sometimes be ordered for protection from agents that pose only an inhilation hazard, like CS and CN.
Figures that are modeled in CPOs would have M17-series masks, in BDOs they could be in M17 or M40 masks... AFV crewmen would be modeled using M24 masks until about 1992 when they were issued M-42 masks and other personel used the M-40.