Volition released their second DLC pack for Saints Row IV today, aptly naming it the GAT V DLC on the day that GTAV releases (Coincidence? I think not.). It's available for purchase on consoles, Volition has it released the DLC Pack on PC for free for September 17th, as another knife into GTAV, which has not been announced for PC.
The GAT V pack is another costume pack, allowing gamers to dress up as Johnny Gat and Aisha. Their other DLC pack, The Wild West Pack, was also a costume pack with a cowboy outfit, wild west dress, and a Western-styled shotgun and revolver.