Graootoly Description:1. Material: Plastic + Metal2. Built-In Battery Capacity: 300 Mah3. Type: Teaching Loudspeakercolor: BlackPackage Contents:1 x Transmitter1 x Receiver1 x Head Mount1 x Adapter1 x Charging CableNote:Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The UseOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.