Castrol professional Vs Castrol Edge

[xrblue]

Hi all
I used the Oil finder tool on the Castrol website.
It recommended Edge 5w30, but if I select Professional workshop owner it recommends 0w20.
I know what the figures mean but does anyone know why a thinner oil is recommended for professional?

Thanks

Edited by xrblue on Thursday 5th December 23:05