Kohei’s started surfing on single fin surfboard , so when he started to shape, his first designed template and shape was also a single fin. But then, longer & thicker single fin design got shorter around late 70s to be able to turn more on the face. He went as short as 5’3” , to ride double over head surf. Twin fins & 2+1 stabilizer design came & gone as soon as Thruster was introduced by Simon Anderson, then all else was sort of disappeared from the surfboard rack.He shaped thrusters only for over 10 years, every day. Looking back for that era in shaping & glassing room, it was a simple but repetitive time which is very different from recent days. 80’s thruster design had wider tail and volume, so it was not too difficult to ride for any level of surfers. But as the surfing progressed with surfers like Kelly Slater & Rob Machado in the 90’s , it got narrower, thinner, razer sharp & curvier, often looked like potato chip. For the average Joes, the product was even hard to balance in waiting position, let alone catching waves...It worked better in good , bigger wave conditions, but created a difficulty time for the beginners.Also, 90’s brought back Long board that started different aspect of styles to the beach. Kohei remember it was a bit of a strange time to see 6’1” potato chip in between 9’0” long boards.