The Ozlo Sleepbuds are in-ear sleep devices that use passive noise isolation and sound masking to reduce environmental noise during sleep. They were developed by former Bose engineers and use the same core acoustic approach as the discontinued Bose Sleepbuds. Each earbud contains small biometric sensors that detect when the wearer falls asleep. When sleep is detected, playback automatically transitions from streamed audio to built-in masking sounds stored in the earbuds. The white noise and ambient environmental sounds help cover background noise like snoring or outside disturbances. The earbuds connect through a Smart Case that functions as both a charging base and a Bluetooth LE (Low Energy) bridge between the earbuds and a smartphone. Typical operation allows for about 10 hours of use per charge, and the Smart Case provides several additional charges before it needs recharging. The housing is made of soft silicone materials with a low-profile shape that minimizes ear pressure. This design allows the earbuds to remain comfortable for extended wear, including for individuals who sleep on their side.