Comments about Camelbak Racebak Hydration Vest for Men - 72 oz. Reservoir Included.:

This hydration kit is made to be worn by itself, or under another shirt. I recommend, as a guy, wearing something over it so you don't look like you are wearing a sports bra.

Once you fill the bladder and place it in the shirt, you put the shirt on just like any other shirt, although a bit tighter.

Running with it is comfortable enough, though the tube can be slightly annoying as it bounces back and forth on your right pec. Another downside is on the fly adjustments require help from a friend; this is because, once wet (either with sweat or a leaky hydration bladder), this shirt is nigh impossible to remove quickly.

Despite the cons of this item I would still recommend it IF you're looking for something lightweight and chafe-free.