Bay horses and 'ears' colours

Um, well apart from not really following the question, do you mean a fly bonnet?
Mine has a steel grey/blue but only to match the browband not her ears.
 
That's the type I have, I just call them bonnets :)
I will be selling my cob one as her bulbs don't fit in properly-colour in August Ear Shots in Cafe.

If its for leading in, the same colour as your headcollar
 
Two of ours wear them for showjumping, both incidentally are bay (well one bay and one dark bay). Theirs are dark blue and they look really smart in them. I think darker colours look more classy on darker horses. If you want it to stand out a bit more I think dark colours with white trim look super smart too.
 
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