Tekit Sports Wireless Bluetooth Speakers Dustproof Shockproof Subwoofer Speaker Boombox NFC Power Bank for Sports Camping Hiking for most Phones and Laptop Water-proof and sand-proof design: Safeguards the speaker against water submersion, plus dust and other small particles, so you can listen to music both indoors and outdoors Built-in microphone: Enables use as a speakerphone, so you can enjoy hands-free calling Built-in rechargeable 3.7V, 3600 mAh lithium-ion polymer battery: Provides extended playback, enables you to stream music for up to 12 hours on a full charge Near Field Communications (NFC) technology which allows for easy, one-touch pairing by simply tapping your NFC-enabled Bluetooth smart device on the speaker. Wireless Water-resistant Shockproof Dustproof Portable Bluetooth Speaker for Music Streaming via Bluetooth V4.0 Technology, compatible with most Bluetooth-enabled devices