There are many styles, sizes, colors and types of pop gear on the market. Some are big, some are small. They usually consist of a series of spinner blades spaced along a piece of lightweight stainless steel cable. A small rudder is attached to the front of the wire to prevent the entire mess from rolling over. Without the rudder, the wire would end up twisted into something that resembles the mess on top of my computer work station.
Pop gear is flat-out effective.
Tell that to a guide who's trying to put fish in the boat. You can cover more water than you can while still fishing. You can vary trolling speed to entice strikes. And if fishing is dead, at least you're seeing some different scenery. There are some tricks to making trout on the troll bite.