The video showcases the product in use.The video guides you through product setup.The video compares multiple products.The video shows the product being unpacked. KIMAFUN 2.4G Fitness Headset Wireless Microphone Merchant Video Previous page Next page 1 Ergonomic Design 2 Excellent Sound Quality 3 Automatic Pairing 4 Long Battery Life 5 165FT Wireless Distance Previous page Next page When using this wireless system with my speaker, there is a sudden howling. 1) Please adjust the position of the transmitter and speaker. Do not point the microphone directly at the speaker. 2) Please try turning off the reverb and turning down the volume of the speaker. This wireless system doesn't work with my Bluetooth speaker. This wireless system is not compatible with portable mini speakers with Bluetooth only. Please choose a speaker with more than 15W power and a 1/4'' or 1/8'' microphone audio input port. The actual transmission distance is less than 50M(165FT). Obstacles will reduce wireless signal transmission. In an open area, the transmission distance can reach up to 50M. Please try to remove obstacles between the transmitter and receiver. There is noise when using this wireless system. How to reduce noise? 1) Please check if there is a strong magnetic field or Wi-Fi signal interference nearby. 2) Please use the included windscreen foam to reduce noise.