Rod guides and rod-guide inserts are vital components of your fishing rods. Major upgrades over the past decade increased performance via better sensitivity, better heat dissipation and lighter materials. Custom-rod builders are up-to-date with the latest trends, staying knowledgeable when buying new components. But for the rest of us, we likely need a refresher. Not because we plan on building a bunch of rods next month, but because we should understand the features, designs and parts of the rods we’re buying.