MicroWave 18 Line Control System: The new MW18’s offer the most advanced line control for heavier casting applications while specifically designed as a fly rod stripping guide to capture and instantly control fly line for longer smoother casts. The MW18/8 offers an 18mm secondary ring with an 8mm primary ring in 4 configurations; Single stripping guide option, double foot 8mm running guide option, single foot running guide option and an HD single foot option in Polished or the new “Black Diamond” frame finishes.