help with 5th slot

iv noticed that 5th slot is in a couple of new hacks but when i use it in game i click on the weapon slot it comes up with a red box then i go into a game and notin happens how do u use these hacks???

go in item shop , buy some other weapon and then click 5th slot the add it to the 5th slot so you have 2 weapons (on combant for example , wepon on 3rd slot and another one on 5th)... for 6th slot i dont think you can equip any weapon but i could add adrenaline there