Tele Vue offers the Bandmate Mars Type A

Enhance your view of Mars opposition coming up soon!

The Bandmate Mars Type A is a dual band filter with differing dielectric coatings on each side of the substrate, and as a dual-band filter it permits green and red to pass through while rejecting all other visible color.  The Type A enhances detail on the Martian surface, without disturbing the natural color of the polar caps or other parts of the surface.  The Type A provides an extremely natural view, and is highly recommended for 'public' viewing.

Because Mars is so very small, you should choose a very short (<5mm) focal length eyepiece to observe it and reserve extended study of the Martian landscape for the moonless nights of best seeing conditions.