Best colour hi viz

It depends on so many factors. The colour of your horse (orange not so good on a chestnut, yellow not great on a palomino / dun even pink can blend in with some bays), the sorts of environment you ride in (e.g avoid yellow around rape fields), the time of day (orange isn't great with a setting sun) the time of year (yellow not great in summer due to bright sun, orange not great in autumn due to orange/brown leaves on trees) the weather conditions (yellow not good if foggy/misty - although you could argue you shouldn't ride at all then) Pink is probably the one that accommodates the most situations although I think in the situations in which yellow is ok, it is the most visible. I have both pink and yellow and use them accordingly.
 
My coat and hat silk are pink, my tabard that I wear over my coat is yellow and all my other items are a mixture of yellow/orange/pink. I tend to wear all three colours each time, I have leg wraps in all colours so they are different each day. I have orange stirrup iron covers on all the time. My black mare has a yellow/pink neckband and my chestnut has a yellow one. The two tone one stands out much better (my chestnut only goes out in company and always follows, otherwise I would upgrade hers too). I also have hi vis green ribbon on the end of my whip, which is a good eye catcher for drivers.

If I'm riding in woods at this time of year I don't tend to use my orange leg wraps. If I'm riding along rape I don't tend to use the yellow.
 
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