The IZZY Circular 40W T9 Fluorescent Tube Light Bulb in Cool White light colour and 4000K colour temperature is designed for indoor use. With a high energy efficiency rating of A and a long bulb life hours of 10000, this fluorescent tube offers bright illumination with 2800 Lumen output while using less energy. The bulb features a single pin connector and comes in a pack of 1 unit, making it a reliable and eco-friendly lighting solution for various indoor applications.