The bonus sets of gear are variants of sets that are already in the game. They come with the Overkill Edition DLC.
Overkiller is a re-textured variant of Spec Ops, and appears to have pads made of molten lava. It comes with the Overkill facemask and the Double-D Shotgun.
Full Auto is a recoloured variant of Extractor. It comes with the Polymer facemask and the TAH-9 machine-pistol.
Dia de Los Muertos is a recoloured variant of Biker, with the sleeves removed. It comes with the Dia de Los Muertos facemasks and a matching custom-skinned AK-47.
The Meat Shield set of gear is also a re-textured variant of the Spec Ops gear, although the pads appear to pulsate.
The Salem, Rios and Executive Rios sets of gear change the bicep size, and overall weight of the player character.
Each set of gear, apart from the bonus sets and the Skullcandy and Heavy Gunner sets, are seen being worn by the TWO operatives in Mexico.
The Spec Ops, Meat Shield and Overkiller sets mirror the tattoos from the operative's right arm.
The Full Auto, Extractor and Biker gear sets are the only ones gear that totally cover the operative, and therefore hide all tattoos.