A halogen lamp H4 is a type of bulb commonly used in vehicle headlights. This lamp offers bright white light and is favored for its efficiency and long-lasting performance. The H4 features two filaments, allowing both low and high beam from a single unit. It is easy to install and replace. The design is robust and vibration-resistant, making it ideal for automotive use. Due to its versatility and reliability, the H4 is a popular choice for both personal and commercial vehicles.