In-ear headphones from B&W that both fit well and have good sound isolation. They are also water proof and can handle both a rainy day and a sweaty workout.
From Electricshop
Bowers & Wilkins PI7 S2 True Wireless Noise Cancelling Earbuds Canvas White
John Lewis & Partners
Bowers & Wilkins Pi7 S2 Noise Cancelling True Wireless In-Ear Headphones with Mic/Remote
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