Selling a few cans of R12. On older steel cans like these it is easier to skip using the top port/tap and just use a Robinair type can-tap on the side of the can.
R12 Tips:
Do not use cans of R12 that include additives like an oil charge or a dye. It will say it on the front of the can. Those oils and dyes are completely degraded now and will only contaminate your system. Those oils and dyes are also old tech. If you need dye just buy the new stuff and add it separately. Use modern oil like PAG100 "D.E.C." instead of mineral oil. PAG100 "DEC" is exceptional because it works with R12 and R134a. No other oil can do this. The advantage of this oil is if for some reason you get stuck later on and can only get 134a you don't need to change/drain or evacuate the oil because DEC is compatible with both.
Why R12 is the best:
If you run anything else besides R12 in an R12 system you are losing at least 25% of your cooling capacity. Your vent temps need to be in the low 40F's in order to keep up with TX summers. R12 is also much more efficient, runs at much lower pressure and is less likely to leak out due to larger molecule size and lower pressure. R12's superior properties is why you can find R12 systems that have never been opened up that are still functioning to this day. If you do your AC properly it should be one and done. Spend the time and money. Weak A/C is the #1 reason a perfectly good older car gets parked long term. A nice cool car also means you will have more passengers more often.