The Yomega BRAIN is the original Auto Return Yo-Yo! It rose to popularity in the 90s and has been a staple beginner yo-yo ever since. Featuring a centrifugal clutch system - or 'Brain' - when the yo-yo is throw hard enough, the Brain will disengage, allowing the yo-yo to spin freely at the end of the string. As the yo-yo slows down, the Brain engages again and returns the yo-yo to the hand automatically. An excellent yo-yo for beginners, not only is it easy to wind, but if the yo-yo is thrown gently it will simply perform the basic down-up motion, so fantastic for younger players (although we wouldn't recommend it for anyone under 4). Specifications: Diameter: 58.7 mm Width: 35.7 mm Gap Width: 4.80 mm / .19 inches Weight: 59 grams Bearing Size: Yomega Plastic Transaxle Response: Starburst Response (Raised Plastic) Material: Plastic