1. Durable Material The yo - yo string is made of cotton rope material, which is durable. 2. Features The yo - yo replacement string is flexibly designed to fit various types of yo - yo models and sizes. 3. Yo - yo String Length Each yo - yo string is 100 centimeters (39.37 inches) long. Before playing with the yo - yo, you can adjust the string length according to your needs to get a better playing experience. 4. Easy to Install Installation and replacement are relatively simple, and children can operate it on their own. 5. Scope of Application It is a suitable replacement string for responsive and non - responsive yo - yos. 6. Specification Description - **Material**: Cotton rope - **Size**: Length 100 centimeters (39.37 inches) 7. Package Contents Optional packages: 12 or 10 yo - yo strings 8. Notes Due to manual measurement and display differences of monitors, slight errors are acceptable.