All Profoto Softboxes have interchangeable diffusers allowing you to choose and switch between different levels of softness. The Profoto Softbox 1x4-Feet Diffuser Kit 1.5 f-stop is designed to soften the light and create a more even distribution, reducing harsh shadows and creating a beautiful, natural look. The diffuser can also be used as a neutral density filter when, for instance, you're working with low apertures or long exposures. The different diffusers span from 0.5 f-stop, which provides a slightly softer light, up until 1.5 f-stop, creating more effective softness to the light. All diffusers are easy to install and remove, with Hook-and-loop Fastener attachments, allowing you to quickly switch between different setups. It comes in a labeled soft pouch. All Profoto Softboxes come with a Diffusor 1.5 f-stop. They are incompatible with the RFi, OCF, and Clic Softbox ranges.