We can identify two primary problems with clip on bars. First, when fitting them on standard road drop bars for a triathlon or time trial, we have to adjust the whole geometry of our cockpit. Second, they cover the flats. The Airstryke Aluminum Clip on Aerobars take care of the second issue by including Profile Design's ZB Flip Up brackets, which use springs to keep the armrests elevated while you're not resting on them. This preserves access to your drop or basebar's flats without sacrificing the benefits of clip on aerobar extensions. As for the cockpit adjustments, we're afraid you're on your own, though we do know at least one athlete who slides her saddle forward a random distance and calls it good.