The thinnest UV resin available from Loon, Flow is thin enough to work as a head cement replacement, but strong enough to coat heads, bodies and midges. Cures within seconds when exposed to Loon's UV Mega Light or UV Power Light.0.5 fl. oz.Ultra-thin UV-curing resinAllows infinite work timeCures instantly when exposed to UV lightCures hard and clearCan be used as head cement replacementIncludes brush applicator