Zealot S1 4000mAh Waterproof Bluetooth Bicycle  Power Bank Speaker with Accessories - Blue BEST BICYCLE SPEAKER: Mounting S1 on your bikes handle-bar, keeping Bluetooth connected, music playback and hands free phone call is all along the way with you; Pressing the power button, S1 turns to a torch light(3 SOS light modes) to enlighten your way; Supporting FM radio and TF card music playback, S1 never let you feel lonely on the go; Whats more, S1 can be used as a external battery/power bank, its a super Transformers and couldnt be a better companion on your bicycle. STUNNING & STRONG SOUND:Built-in 40mm drivver, Neodymium stereo amplifier presents you live experience in talking on phone and surprising fullness, excellent sound resolvement gives S1 gorgeous timbre way above average. LONG BATTERY LIFE: 4000mah rechargeable battery provides a long time usage (up to 24 hours by TF card play) and turns it into a backup power supply as well, perfect portable wireless speakers for biking, travel, cycling and other outdoor activities. FULL-EQUIPPED OUTDOOR ACCESSORIES: ZEALOT considerately offer all you need when cycling with S1 - Bike mount & Carabiner & Audio Cable & USB Charging Cable & Silicone protective sleeve to ensure waterproof, dust proof and shockproof TIPS & WARNING: 1, To receive stronger FM signal, please be advised to plug charging cable into the micro USB port or plug in the AUX cable as a radio antenna. 2, The USB port is output for backup power supply, to juice up your phone or other devices, DO NOT insert U-disk into speaker