Richard J Kinch wrote:
larry moe 'n curly writes:

IOW it appears that there's nothing in the can except propellant and
some silicone compound.

It's 87 percent heptane, which is a petroleum distillate. The CO2 is the
propellant.

Yes, CO2 is the propellant. But the Heptane is just a solvent to help
thin the silicone and allow it to penetrate. It evaporates rapidly,
once it's out of the can, leaving the silicone lubricant evenly
dispersed.