The tight weave contributes to the heft

Storage pockets

Whatever the mission

Worth mentioning is also that silnylon is somewhat elastic

Current: 7

3M 6009S Mercury Vapor/Chlorine Gas Mask Filter – NIOSH Approved Waterproof The tight weave contributes toProtect yourself from hazardous airborne contaminants with the 3M 6009S Mercury Vapor Chlorine Gas Mask Filter. Designed for industrial and emergency preparedness, this NIOSH approved filter provides reliable protection against mercury vapor, chlorine, sulfur dioxide, and certain particulates. NIOSH Approved Protection Defends against mercury vapor, chlorine gas, and sulfur dioxide. Passive End of Service Life Indicator (ESLI) Alerts when replacement