Summer line on an ice reel behaves like a spring. A tiny spool and freezing air give mono a coil it will not let go of, so the line hangs in loops above the jig and a light bite never reaches the rod tip. Ice line is made thin and soft so it drops straight. That is most of the job.
For a jigging rod aimed at panfish and perch, spool 2 to 4 lb ice mono like the Berkley Micro Ice and you are done. Move up to 6 or 8 lb, like the Sufix Ice Magic, for walleye or near timber. Fluorocarbon sinks and is hard for fish to see, which helps in clear water, but it is stiffer, so most people run it as a leader. Ice braid has no stretch and shows every tap, but it soaks up water and can freeze in the guides outside a heated shelter. Tip-ups are a separate job: 20 to 40 lb braided tip-up line on the spool and a leader at the end.
Tom has not fished these lines through the ice. The picks are ranked from what each Amazon listing states, Amazon buyer ratings and AI-assisted research, and no brand paid to be here. The Sufix Ice Braid has the highest buyer rating on the page, 4.7 stars from 104 Amazon ratings; the Berkley Micro Ice has the most history, 4.6 stars from 568. For the rest of a first ice kit, the beginner ice fishing gear guide is linked just below.