HFC 134 is the stuff used in Duster gas (not anymore). The stuff you want is tetrafluoroethane. However most companies that make duster gas for the consumer market use Difluoroethane.
Don't worry about using duster or propane just get some propane. A lot of people don't even upgrade their slides and run propane fine (however this creates more wear and you'll eventually have to replace the slide). Slides are not a restricted part, it's actually the frame that's restricted on pistols so yeah.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE