This really is a good idea to wear all year round.
Equisafety have never come across a riding hat that it does not fit. It has elastic in two parts which means it fits most hat sizes. On the inside is a sticky rubber that grips onto the hat, to make sure it does not ping off if your head knocks a branch, it does not damage velvet hats.
The fluorescent EN1150 tape is 100% reflective and fluorescent. Wipe clean with a cloth.