We're big fans of this style of split CDC wing! It's buoyant, visible at distance and realistic to boot. This emerger from Antonio Rodrigues is a good option when you've got fish rejecting higher-floating offerings.
Here's what Antonio has to say:
"This pattern uses a Hi-Vis spot to help us anglers to see it in tough light conditions when using smaller sizes. This pattern is being successfully used in Europe and the USA for trout and grayling from pocket to slow water pools especially during PMD, BWO and March Brown hatches."