The game has 6 different item slots: 1 for weapon and armor, 2 for gear, and 1 for gloves and boots. There are free items that can drop to all players from any enemy or shop crate, and premium items that need to be unlocked for them to start dropping. You can unlock premium items through the paid Battle Pass, or through the Crate Special on the main screen. Once you unlock a premium item, it will start dropping from the enemies and regular crates.
The following items are free and will drop to all players from enemies and crates:
Weapon: Auto Handgun, Blaster, Laser Rifle, Plasma Cannon
Armor: Body Armor, Heavy Armor, Necroshield Suit, Ninja Garb, Tactical Suit
Gear: Dum-dum Bullets, Explosive Bullets, Iron Sights, Scope
Gloves: Combat Gloves, Tactical Armguards
Boots: Ninja Tabi, Tactical Sneakers
To see an up to date list of the premium items, click on the Catalogue button from the main screen of the game. From the Equipment tab you can view all of the items that are currently in the game.