The sk-db400 by studioking is a diffusion bulb with a diameter of 40 cm. thanks to the extra large diameter, the light in the sk-db400 is distributed very evenly over the surroundings. you easily connect the sk-db400 to the light source, thanks to the standard linkstar/bowens connection. this s-bayonet is not interchangeable. the sk-db400 is made of plastic, making the diffusion bulb durable and able to take a beating. the adapter for connection to the flash protrudes approximately 6 cm from the diffusion sphere. Application sk-db400 If you use flashlight and want to prevent hard shadows, the sk-db400 is an ideal tool. think of taking passport photos and studio portraits. the sk-db400 is also a good option for fully lighting a large space, such as interior photos of real estate agents.