Scientific Anglers have been building fly lines for 70 years. They know a bit about what makes a great fly fishing line. S/A lines are also some of the most durable lines available today. Amplitude Smooth Series Fly Lines feature the same AST Plus Slickness that has proven itself in the original Amplitude lines now in a smooth fly line format. Same great slick shooting, durable finish without the texture feel. Amplitude Smooth kicks of the series with 6 offerings including your favorite tapers such as Titan Long, Trout, Anadro, Grand Slam, Bonefish and an all New Infinity. Amplitude fly lines feature ASTplus which provides a hard slick coating for durability and reduced friction for distance. Sonar is a new name for an entire series of sub surface fly lines. In the Sonar series you will find everything needed to fish streamers for trout to big flies for musky to saltwater for striper to tropical big game. If you need to go sub surface Sonar will get you there! Mastery Series lines have a long reputation as long lasting, high performing lines.