Asics Womens Race Singlet.
This racesingletenables you to run freely. Its a no-frills top that will keep you cool through the whole run.

As for comfort, the flatlock stitching and seams on the back cuts down on chafing and aids comfort.

It features Motion Dry, whichis a fabric construction that wicks sweat from your skin between fibres in the fabric, keeping you both dry and comfortable.