Tank bag

[IffyBiker]

Not yet technically challenging question really - but my tiny brain can cope with this one.
Anyone recommend a decent tank bag? Was thinking rear top box but I don’t want to spoil ‘The Admirals ‘ good looks 

[Hugh Mungus]

For a start... Large or small? There's so many different styles and sizes.

[Creaky]

Kriega

[ratkinsonuk]

Oddly, I've just bought this Givi 3 litre bag to store phone, passport, etc in when touring. It uses the Tanklock system. so a pretty decent buy for £56...
https://www.ebay.co.uk/itm/132617372482
Rob