Amazon.com: Unresponsive Yoyo Professional, Aluminum Yoyo for Kids, Beginner Yoyo Ball, for Advanced Yo-Yos Players with U Type KK Bearing + Yo-Yo Storage Bag + Glove and 10 Replacement Yoyos Strings :
Magic YoYo 10-Ball Concave (KonKave) Bearing Size C by YoYo Shop Australia