UNLIMITED TALK TIME: Never worry about a dead battery again! Thewalk and talk wire free up to 350 feet in your office, without a cord to get in the way. Compatible with your corded desk Discover D904 has a spare battery charging compartment that allows a second battery to charge at all times. So, when your first battery no longer has a charge, you simply switch it out with the second battery and your back to full charge! | WIRELESS FREEDOM: 350 feet of wireless freedom to walk and talk on your phone calls with DECT technology that ensures your conversations stay private in even the most secure environments. | ALL DAY COMFORT: Included with a headband and 3 choices of ear hooks the D904 wireless headset can be worn all day long | SEAMLESS CONNECTIVITY: Whether you want to connect to a desk phone or computer, the D904 provides you one headset for both applications. To answer/end calls away from your desk phone a Lifter or EHS cable will be required (SOLD SEPARATE) contact seller to verify compatibility | 3X THE WARRANTY OF OTHER BRANDS: You're covered with a 3 year warranty (covered from Headset Advisor) for peace of mind in the case of a defect. Replacements are quick, there's never any paperwork to fill out and return shipping is always free