1x 55W OSRAM Dimmable 2GX13 4 Pin, T5 Round, 300mm Circular Light Bulb 2GX13 4 Pin Base, Colour 4000K This lamp has 2 pins on the inside and 2 pin on the outside. Brand New 8,000 hours average lifespan; 4000K cool white. This bulb is dimmable. These bulbs are approximately 300mm with a tube thickness of 16mm. Circular fluorescent lamps are low energy bulbs and one of the most popular choices for ambient lighting, particularly in areas such as corridors and stairwells. Being almost circular, they are a great alternative to linear fluorescent tubes; compact, bright, they provide a good all-around light. Product benefits Excellent uniform illumination with no shadows. Areas of application: Public buildings, Offices, Restaurants, Industry, Shops, Supermarkets and department stores, Hotels. Product features Good color rendering index. Single-ended round fluorescent lamp. Dimmable.