Luminous Responsive Yoyo, yoyo balls glow K1-Plus come with regular flating bearing made by ABS, Style String Trick (1A, 3A, 5A), Durable and has high performance Keep The Noctilucent yoyo under the light or in the sunlight for a few minutes to charge the glow effect Heavier than before, and have more fun without weighting rings. A perfect toy for kids, friends, families, etc; Recommended for Kids Daily Practicing or Competition. If There is A String Get Stuck: 1.Remove the string firstly 2.Take a look at whether the ball is loose and the two hemispheres must be tightened well 3. Attach the string properly.(The most important thing) Applicable moves: (1A, 3A, 5A) Weight: 65g Diameter: 51.03mm Ball width: 41.01mm Shaft width: 4.38mm Bearing: 8-ball U-shaped shaft Screw: M4*16mm Colour:blue Material:ABS Package Contents: 1 * ball 1 * gloves 1 * velvet bag 5 * rope (random color, specified color not accepted) Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.