This is a gradient mobile often used in Montessori education. I am selling it because I no longer have the opportunity to use it. 【Safe and Secure Materials】The wool ball pendant hanging on the bed contains no harmful substances and is very soft to the touch. It is also lightweight, so there is no worry of it falling and hurting your child. 【Supports Sleep】By swaying the wool balls to attract your child's attention and increasing the number of times they turn their eyes, it helps prevent strabismus and also induces sleep, helping them fall asleep faster. 【Cultivates Color Sense】The color gradient of the wool balls shows the change from dark to light within the same color family, helping children develop their sense of color and cultivate a sense of beauty by observing subtle differences. 【Multi-functional】Suitable for hanging in places such as strollers and cribs. It is also suitable as interior decoration for a children's room when not in use. 【Product Size】Product size: 40*20cm (see photos for details); Material: cotton, felt wool, wood; Weight: 16.5g; This product comes with a quality guarantee, and we conduct various inspections of the product before shipping. If there is a defective product, please do not hesitate to contact our store. We will do our best to accommodate your request.