Canon EOS 40D High Grade Multi-Coated, Multi-Threaded, 3 Piece Lens Filter Kit (55mm) Made By Optics

UV Filter (ultraviolet) Haze (1A) for protection against dust, dirt, scratches, fingerprints and the sun's ultraviolet rays.
Circular Polarizing Filter. Used to increase color saturation, like darkening blue skies so that white clouds stand out.
FL-D Filter (fluorescent) for taking pictures indoors under fluorescent lights.
This filter removes the greenish tint given off by fluorescent lighting.
Compact protective carrying case for transporting and storing your set of filters.