PAS Rack Banjo Bolt Size?

[CerbWill]

Hi all, there seems to be a flurry of PAS questions at the moment, unfortunately I'm unable to find the answer to my particular issue. My rack appears to be leaking from the banjo bolt on the rack. Not too surprising as its only covered a few hundred miles since I refitted it.

Does anyone know what size the banjo bolt securing the high pressure line to the rack valve body is so I can buy some replacement washers before taking it apart?