JBL Endurance 300 Bluetooth- The JBL Endurance 300 Bluetooth are supremely comfortable with FlexSoft ear tips and TwistLock technology, these secure fit buds were designed from the ground up to amplify your workout. They're guaranteed never to hurt or fall out, while touch controls let you easily manage music and MagHook lets you secure them conveniently close at hand when you're done using them.