Key benefits Simple, allinone control: Use a single knob for volume and track navigation plus the M key for source selection, reducing the need to search for multiple buttons. Quick, tactile power control: Turn the lever clockwise to turn on and counterclockwise to turn off for fast access. Flexible playback options: Supports Bluetooth, TF card, FM radio, and AUX inputs for versatile listening. Efficient source switching: Cycle through audio sources with a single press of the M key. Reliable operation: Clear, responsive controls designed for everyday use. Controls and operations Previous song: Doubleclick the knob. Next song: Click the knob. Volume control: Turn the knob to increase or decrease volume. Audio sources: Bluetooth, TF card, FM, AUX. Switch sources by pressing the M key to cycle through. Power on/off: Turn the lever clockwise to turn on; turn the lever counterclockwise to shut down. Compatibility and inputs Audio sources supported: Bluetooth, TF card, FM radio, AUX input. Source switching: M key cycles through Bluetooth, TF card, FM, and AUX as available. Use scenarios In a car or at home: Use the knob to skip tracks and adjust volume while driving or relaxing, and switch between Bluetooth streaming, FM radio, TF card, or AUX as needed. Outdoors or on the move: Connect via Bluetooth to a smartphone for music or calls, then switch sources with the M key without removing hands from the main control. Desk, workshop, or study area: Use TF card playback for offline audio content or music while working, with quick access to Bluetooth or AUX if a device is nearby. Specifications and notes Audio source options: Bluetooth, TF card, FM, AUX. Control methods: Knob for track navigation and volume; M key for cycling audio sources. Power method: Lever to turn on clockwise, turn off counterclockwise. Size and material: Refer to product specifications for exact dimensions and materials. Performance: Designed for clear, straightforward operation with minimal input required to control playback and source selection.