Dear friends, welcome to our shop!All of our products are carefully selected for you. The design of appearance is excellent enough and the quality is hard enough. If you want to have more choices of styles, you can enter the seller's information and select them slowly. Our products can absolutely meet your needs. I believe you can find the products you like!-Connection mode: Bluetooth / TF / USB connection-Bluetooth version: 4.0-Interface type: USB type-Power supply mode: built in lithium battery-Output power: 3W-Signal to noise ratio: ≥ 65db-Duration: 3-5 hours-Approximate length: 77mm*40mmNote:1. Due to the differences between different monitors, the picture may not reflect the actual color of the item. We guarantee the quality and style as shown in the picture.2. Due to manual measurement and different measurement methods, please allow 1-5mm deviation. thank you!3: Our store will update a lot of this type of products every day, if you want to browse more beautiful, preferential products, you can click our seller information to follow us! Hope our products can create a more comfortable, simple and happy living environment for you, thank you!4. If you think our products are very good after you purchase and use them, please leave your comments and feelings, or show your style on Facebook, twitter and Youtube. Your satisfaction makes us move forward! a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a