Dow Corning Q4-2805 fluorosilicone channel sealant is as a groove injection sealant for aircraft fuel tanks. It can also be used in applications that require a non-curing sealant. During tank fabrication or maintenance, this sealant is directly injected by an air gun into the grooves of integral tank systems. - When exposed to aviation fuels, this channel sealant will swell just enough to tighten the seal. This is a useful characteristic especially when the expansion of fuel and fuel vapors might cause internal tank pressure, which can happen as the result of aerodynamic heating.