Federal Ultra Steel, FLIGHTCONTROL FLEX WAD, 20 Gauge, 3, #2 and #4 Shot, 1oz, Zinc Plated Steel, 25 Round Box PWUX209 24 Waterfowlers live for those moments when the birds do it right. And in those moments, they want a shell that does the rest. Federal Premium Ultra Steel blends the rear-opening FLITECONTROL FLEX wad with a payload of our best zinc-plated steel, producing extremely tight patterns for even deadlier performance. Available in a variety of standard payloads, as well as loads that feature two sizes of shot: smaller pellets that create full patterns and larger ones that deliver better lethality.