For Safety's Sake
Safety is a super important issue when bike riding, especially at night. You need to maintain a certain level of visibility at all times to ensure that drivers are aware of your presence.
Most people achieve this by wearing bright colors or reflective vests. But if no one ever wears anything different, it becomes a sort of white noise, easily ignored.
But who's gonna ignore a lady wearing nothing but one of these bras while riding a bike? No one, that's who. You'll certainly get a lot of attention, some you may even consider unwanted. But is there really such a thing as unwanted attention where safety is concerned? If you make the news at 10, you should just consider that a win.
Don't think we've forgotten about you, gentlemen. Your safety is just as important to us. So you'll be glad to know that these bras are especially effective for bike safety when worn by males.