• Plastic, sponge
• Balance tool-- designed to ensure optimal compatibility with surf kayaks, being for sup
• Fin box balance tool-- the fin box will your sup's tracking, meaning less stroke changes. for better stability and control
• Sup fin box-- the fin box is suitable for various kinds of fin, stand up sup and more. easy replacement and repair of plastic fins for sup
• Fin box sup fin box-- this fin box sup fin box can the stability of fin box to keep safety of you when surfing
• Fin box balance fin box-- the fin box is with the simple design is easy to use and install, and can meet your various needs