This Cokin Color Back Filter - Blue includes 2 filters. Use one over lens and 2nd complimentary filter over the flash for some amazing effects. Things in the foreground of the picture will be dominated by the light from the flash and be more amber toned. Things at the focal point will be correctly exposed and color balanced. Those things in the background will be dominated by the filter over the lens and hence tend more toward blue tones. *Note: included is a plastic piece for protecting the filter, a filter for aiding in flash and a small case.