Multifunctional Karaoke System: SDRD-307 has built-in Bluetooth 5.0, and the working range is up to 33 feet. Easily connect to Bluetooth, AUX, TF/USB inputs. It can record audio stream through a microphone inserted into a USB/TF card. In addition, the USB port supports the power bank function to charge your smartphone/tablet.Multiple sound field effects: ALPOWL karaoke machine can turn sound field effects into standard, pop, rock, classical, treble, bass, SDRD-307 becomes a karaoke machine to share with your family and friends.Powerful PA System: Built-in 2*15W speakers, multifunctional design, can reproduce full-range stereo. It makes the bass stronger and more balanced, and the "Voice Cancel" feature lets you cancel the singer's voice with one touch.LONGER BATTERY LIFE: Built-in rechargeable high-capacity lithium-ion battery for speaker and high-capacity lithium-ion battery for microphone, can play music for up to 3.5 hours non-stop at maximum volume. The speakers act as a charging station, so they can be easily charged at the same time. And with a stable wireless signal over 80 feet, you can sing as much as you want.100% Customer Satisfaction GuaranteeIf you have any questions, please feel free to contact us, we will always replace defective products or refund within 45 days.