Browning Invector Plus Prairie Storm Choke Tubes The unique FLITECONTROL® wad in Prairie Storm™ Ammunition will deliver inconsistent patterns in ported chokes or when used with wad stopping or stripping devices. This choke uses a special field-tested constriction and length to get the most from Federal Premium Prairie Storm™ Ammunition. Carlson’s Titanium Coated choke tube allows Federal’s special FLITESTOPPER lead pellets and FLITECONTROL® wad deliver devastating downrange patterns. This choke performs equally well when used with lead, copper, nickel, Hevi-Shot and steel shot loads. Carlson’s Prairie Storm™ choke tube is a proven performer on pheasants and upland birds using all lead and steel shot loads over extended distances. Note: The Late Season choke tube is a Improved Modified constriction All sizes and speeds of Steel shot may be used in either choke tube. - Caliber: Browning Invector Plus 20 Gauge - Constriction: Late Season