Free Battery. Perfect for use in bars and parties. LED Lights: The defining feature of these glasses is the presence of built-in LED lights. These lights can emit various colors, producing dazzling and eye-catching visual effects. LED lights are energy-efficient and long-lasting, ensuring that the glasses can be used for extended periods. Power Source: LED glasses typically have a small battery or power source integrated into the frame. Some models use rechargeable batteries, while others use replaceable button cell batteries. The power source provides the energy needed to illuminate the LEDs. Lighting Modes: Many LED glasses offer multiple lighting modes, allowing users to switch between different colors, patterns, and flashing sequences. The control buttons for these modes are often discreetly located on the frame for easy access.