Chinook | Standard Diameter - US Base Cup - Extensions - Windsurf Carbon Extension-US Cup-SDM-Tall 48cm Product # 16H ¥21000 Carbon Extension-US Cup-SDM-Medium 28cm Product # 18H ¥20000 Aluminum Extension-US Cup-SDM-Tall 48cm Product # 30H ¥15000 Aluminum Extension-US Cup-SDM-Medium 28cm Product # 40H ¥14000 Aluminum Extension-US Cup-SDM-Short 12cm Product # 47H ¥13000 Standard Diameter