Hi guy's

I found a cyclinder of R411b in a cupboard apparently a previous dude bought it to try out as a drop in for R12 or evan a replacement for R134a ,i have never used it before ,is it a replacement for R12 ,r134a and are it's properties similar to R12,
the equipment i us it in would be vending machine fridge's with anything from a 1/4 HP to 1HP compressor's ,cooling the cabinet down to a minumin of +4oC .The cyclinder is full and no one know's if it was succesfully tested or not.

could any of you top notch guy's have any advise weather i should try it or not

cheers