Wireless Speaker Featuring High Definition Bluetooth® 3.0 Technology | Simply Pair Your Device With The Speaker To Enjoy Dynamic Stereo Sound | Features High Definition Sound With A Built-In Microphone For Easy Hands-Free Calling | Perfect For Your Home, Office Or Outdoor Activities | LED Indicator Light | Split Ring Attachment | Features A Micro USB Input (Cord Included) | Up To 1.5 Hours Of Play Time | The Bluetooth® word mark and logos are registered trademarks owned by the Bluetooth SIG, Inc. and any use of such marks by Hit Promotional Products, Inc. is under license. Other trademarks and trade names are those of their respective owners.. Approximate Size: 1 3/4″ Diameter , Imprint Area: 1 5/8″ Diameter