problem in cascade cycle

[next life]

i want to use a R508a on the low stage cycle as an alternative of R503 , i want to know whats the compatible lubricant for this gas (R508a) ?

[beida]

Hi :)
Happy Year Brother
i see many stage cycle R508a All its Come Full With polyolester oil

[next life]

happy new year for you 2 brother
thanks so much for replay :)