Size: 1.25" 5-Position Filter With Four Color Filters 1.25" Superior Quality Multiple 5-Position Filter Wheel and Color Filter Set includes the 1.25" 5-Position Filter Wheel and Set of Four 1.25" Color Filters (#15 Deep Yellow, #25 Red, #58A Green and #80A Medium Blue) for optimized planet study. Color observation filters can dramatically increase planetary detail by reducing the predominant hues and uncovering hidden contrast. One of the most useful tools for observing through different filters is our 5-Position 1.25" Filter Wheel, since it allows you to easily switch between up to five different 1.25" filters without removing the eyepiece you're using.