This is the One-Touch Fin Bolt Quick Snap System 2. The ultimate one-touch bolt, this fin bolt is made entirely from machined stainless steel parts. The one-touch mechanism makes attaching and detaching fins very easy. The built-in spring prevents fin wobble. The fin base is separate and fixed, so the base won't come off, providing peace of mind. Retail price: ¥3,080 Condition: Used for about six months after purchase. There are minor scratches and discoloration, but it can be used without any problems. I have lost the base wrench, so please prepare one at a home center, etc. (1.5mm hex wrench) If you have any questions, please comment and I will answer. Thank you for looking.