Scientific Anglers Amplitude Smooth Infinity Instructor is a line specially developed to optimize fly-fishing instruction thanks to its innovative design. Featuring the revolutionary AST Plus additive, it offers exceptional glide and superior durability. Its slightly heavier profile facilitates the loading of fast-action rods while remaining compatible with a variety of casting styles. Alternating colors every 10 feet allow precise visual tracking, essential for instructors in educational settings. With its extended head, this line ensures long-distance casts while maintaining excellent drift control. Perfect for dry flies, nymphs and streamers, it excels in moderate to cold climates. Delivered on spool only, it meets the needs of experienced anglers and teaching professionals.