Plastic Material: The responsive ball is made of plastic, without toxic elements and unpleasant odors. People can play with it without much pressure, as it is lightweight and portable. Universal Size: The size of the responsive ball is approximately 5.5 x 5.5 x 2.8 cm/2.17 x 2.17 x 1.10 inches, which is a suitable size for people to hold in one hand. Responsive Plastic Ball: You will receive 4 Acsergery gift responsive plastic balls with strings in random colors in a bag, sufficient quality for people to play and use. The string can be neatly arranged when the responsive ball is not in use. Entertaining Gift: As an interesting tool, the colorful responsive ball serves as a great gift for your friends and family. They can have a lot of fun with it due to its challenging and interesting features. Bright LED Light: The interesting responsive ball is designed with an LED light, allowing the responsive ball to emit bright light while spinning. With this feature, the responsive ball can even be played well at night.