The Calus OT3 Pro brings an immersive music experience wrapped in a premium cortical texture charging case that looks and feels elegant and noble. Built for those who want great sound and lasting endurance, the OT3 Pro combines HiFi audio quality with long all-day battery life in a sleek, compact package.
Battery & Charging: Each earbud carries a 25mAh cell delivering 3.5 hours of music at 50% volume, while the 250mAh charging case recharges them up to 3 times — giving you 25+ hours of earbud standby and 100+ hours total standby. Both earbuds and case charge fully in about 1.5 hours.