Features: Electronic Wireless Sound Box Box Science School Projects Experiment Science Toy For Children Education Providing a hands on experience in understanding Wireless technology and sound amplification. Serves as engaging educational tool that learning through practical application. For classroom science project, a family activity, or small learning challenge, Wireless Sound Box Cube set offer a unique opportunity to build and enjoy your own sound . Receive a strong signal, Wireless receiving straight line distance of about 10metres, input voltages 3.3-5V can work for long time (current should be enough) Specifications: Wireless Connection Distance: about 10metres Input voltages: 3.3-5V Size:about 125x68mm/4.92x2.68in Component： Wood Battery: Need Four Dry Cell Batteries（Not Included） Package Includes: 1Set Sound Box Model note: This Set is need four dry cell batteries, it is recommended to buy high-quality batteries, otherwise there will be dead or poor playback sound, due to the limited discharge current of the dry cell batteries, it is recommended that the mobile phone (device) playback sound adjusted to 60-70% or so, but also can be changed to 3.3-5V other current power supply, the sound is better