Caston wireless speaker ST5840

Caston wireless speaker ST5840The Caston ST5840 is likely a portable Bluetooth speaker intended for personal or outdoor use. It would combine wireless audio playback with auxiliary inputs and possibly built‑in charging via USB or solar . The design is probably compact and rugged enough for casual transport. FeaturesFeaturePossible DetailsBluetooth ConnectivitySupport for pairing with phones, tablets, and laptops (likely Bluetooth 4.x or 5.x)Aux / Wired Input3.5 mm AUX-in / line-in for non-Bluetooth devicesMemory Card / USB InputSlot for TF (microSD) cards or USB flash drives to play stored musicRechargeable BatteryInternal lithium battery (e.g. 1,000 mAh to 3,000 mAh range)Play TimeSeveral hours of playback (e.g. 5–12 hours, depending on volume)Charging MethodUSB charging (often 5 V, via micro-USB or USB-C); in “solar” variants, possibly a small solar panelControlsButtons or dials for power on/off, volume, next/previous track, mode switch (BT / AUX / USB)DesignPortable size, light weight, possibly with grip or rubber elementsExtrasLED indicator lights (battery, mode), possibly built‑in speakerphone (microphone), possibly modest water resistance or splash protection