This Ikelite 6148.21 Compact Housing for the Canon PowerShot SX210 IS camera is an injection-molded clear polycarbonate case, known for its strength and corrosion-free properties. The housing offers an unobstructed view of the camera's information and control functions and operates safely to a depth of 200'. Camera installation is quick and simple, and the O-ring seal can be checked visually through the clear housing. The housing is sized and weighted for near-neutral buoyancy and superb handling underwater. A flash diffuser is included to improve lighting quality when the camera's built-in flash is used underwater. For optimum lighting underwater an optional external strobe is recommended. Ikelite strobes are brighter, recycle faster and offer wider coverage than the camera's flash. Being farther from the camera lens, the strobe reduces the illumination of particles in the water which helps eliminate backscatter. The housing comes standard with an optical-grade glass flat port which allows full use of the camera's zoom without vignetting. The Canon PowerShot SX210 IS features a 28mm wide-angle setting. External wide-angle conversion lenses cannot be used to any advantage. For wide-angle work the housing does accept the Ikelite WD-4 Wide-Angle Conversion Dome Port. The conversion dome corrects for the refractive magnification of the flat port underwater to restore the camera's original angle of coverage. The WD-4 and Canon PowerShot SX210 IS combination provides a 28mm angle of coverage with incredibly crisp corners. This option is effectively as wide as and sharper overall than a housed camera with an external wide-angle lens.