The JBL Wave Flex 2 Bluetooth headphones feature 12mm dynamic drivers, delivering exciting JBL Pure Bass sound. The headphones also feature Smart Ambient Awareness technology. With Ambient Awareness, you can adjust how much external sound you want to hear, while TalkThru lets you communicate with others without taking the headphones out of the box. ~ Support Android and iOS (Whatsapp and Wechat message notifications) Bluetooth: 5.3 Dynamic frequency response range (Hz): 20 Hz - 20 kHz Music playback time with Bluetooth: 10 hrs (Playing times with ANC off) Net weight: 4.12 g (Single ear buds), 35.68 g (Charging Box) Accessories: earbuds x1pair, Charging Box x1pc, Type-C USB Cable x1pc ~ • Return and refund are not accept. • Free shipping to HK/Macau when spending over $500 onwards • China area shipping fee $130 + Local SF Express • Two business day shipping. Sent via SF express / JD Logistics. • Exchange of defective units purchased in 7 days ~ *Photo for reference only