Aqua Marina Slide-in Center Fin for iSUP, easy clip in fin to get you set up and on the go in no time. The Aqua Marina Slide-in Center Fin for iSUP's is easily slid in and clipped to secure the fin. Compatible with Aqua Marina iSUPs featuring the slide-in fin-box system, including Breeze, Vapor, Fusion and Monster. Please check your existing fin and fin box before ordering • 8.7” x 7.1” ( 22 x 18cm) • Reinforced nylon. Slide-in installation.