The more, the merrier Add this extra wireless receiver (or two or three) to your Sennheiser Flex 5000 TV listening system so housemates or family members can get in on the late-night TV binge-fests, too. The RR Flex receiver has a 3.5mm stereo output for connecting your favorite pair of earbuds or headphones. Each has its own volume controls, a "Speech Intelligibility" button to boost dialogue, and a battery life of up to 12 hours.