The Blue Fox Vibrax is an inline spinner with one trick the others don't have: a two-part brass sound chamber that spins free of the blade and rings as it turns, throwing off a low hum. That sound is the whole point. It gives fish a way to home in on the lure when they can't see far, which is why this spinner shines in stained and off-color water rather than gin-clear runs.
Sizes 1-4 cover most trout work. Size 1 and 2 for small to mid-size streams; 3 and 4 for big water, high flow, and when you want the blade to track deeper. Silver is the all-around starter and reads well in normal light. Copper warms it up for tannic or low-light water. Firetiger is the loud option for the murkiest, highest flows.
Fish it with a steady retrieve, just fast enough to feel the blade thump through the rod tip. If you lose that pulse, you've slowed too much. Quarter it upstream and across, let it sink a beat in faster water, then bring it back along seams and current edges. It works best at 50-65F when trout are active and pushed into colored, higher water.