One-key multi-function, high-definition call, stereo music, bone conduction acoustic principle, waterproof technology, sun protection, fashion and versatile Model B98 Smart music cap Main feature HD call, listening to music, stereo sound, bone conduction acoustics, sun protection Color Black, white(logo and other colors can be customized) Material Cotton+Polyester+Anlun Size 57CM(adjustable 57 60CM) Craft Waterproof/embroidery OEM requirements "1.OEM LOGO Embroidery/silk printing, MOQ:500PCS 2.OEM gift box, MOQ:500PCS Bluetooth range 15m Without hindrance Control method button Charging method Mirco-USB cable Designed on the left side of the hat sweatband Charging time 2H Listening music 8H Call duration 10H Bluetooth protocol HFP/HSP/A2DP/AVRCP Bluetooth BLE5.0 Waterproof level IPX5 Battery 240mah polymer Support system IOS8+ / Android4.3+ Power on Long press 3s Power off Long press 3s Packaging accessories Bluetooth cap*1, Charging cable*1, Manual*1, Soundproof earplugs*1