The Bluetrek Hummer Bluetooth headset resists sweat, dirt, dust, drizzle, and the occasional downpour; the X-II is shock and water resistant. With extra long talk-time it won't let you down, even when you stray far from civilization. Battery allows 12 hours of talk time and approximately 384 hours of standby. The ear loop keeps the Hummer close to your ear during many activities like running, jumping, cycling and climbing. Removable & adjustable, the ear hook allows the headset to be worn on either ear comfortably. Includes a super-durable, anti allergic silicone rubber ear loop. The control functions include volume up/down, last number redial, voice dial, call reject, answer/end, and mute. Dual color LED to state the status of charge, end of charge, low battery, stand-by and communication.