1,1,1,2-Tetrafluoroethane, AKA R134a, HFC 134a, Fluorocarbon 134a
A commonly used refrigerant. A substance used for heat exchange in refrigerators and heat pumps.
Refrigerant 134a is non-flammable, non-toxic, and non-reactive at normal operating concentrations and pressures. The MSDS does indicate it can still be dangerous under extreme conditions.
R134a is not considered to be an ozone depleting substance, but should be contained and recycled for future use.
I am not a chemist, so if that diagram is bad, /msg me. It should be good now, thanks WolfDave and sirnonya.