From roll the dice v3 (this mod has everything)
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self takeWeapon(self GetOffhandSecondaryClass() +"_grenade_mp"); // This will take smokes and flashes
self SetOffhandSecondaryClass( "smoke" ); // This doesnt GIVE a smoke, it allows you to give other special grenades
self giveWeapon("concussion_grenade_mp"); // This gives you a stun
self setWeaponAmmoClip("concussion_grenade_mp", 2);
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If you want it to remove stun grenades too:
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self takeWeapon(self GetOffhandSecondaryClass() +"_grenade_mp");
self takeWeapon("concussion_grenade_mp");
self SetOffhandSecondaryClass( "smoke" );
self giveWeapon("concussion_grenade_mp"); // Optional
self setWeaponAmmoClip("concussion_grenade_mp", 2); //
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