Hyorin and Bora of SISTAR19 are not the only ones getting ready to heat up summer with their recent pictorials. All four knockouts of SISTAR have now joined together for Ocean World Water Park's upcoming CF!

As the water park's new sexy endorsement models, the ladies show off their bikini-ready bodies in sheer cover ups and shorts, and will leave you wanting to cool off by joining them at the park.

A representative commented, "Soyu, Bora, Hyorin, and Dasom, all have singing ability, stage presence, beauty, healthy figures, charisma, variety show skills, and more. We chose them as endorsement models because they fit well with the water park's special charm of giving thrill and excitement through water-related activities. We anticipate a synergistic effect between the opening of our new water ride, 'Super Wide River', early this June and SISTAR's upcoming comeback."