1. Extra Small Crosshair  - You have to have Small Crosshair first and then you can upgrades it with then making all guns have the Small Crosshair as a pistol with Small Crosshair. I.E. Sniper, Akimbo.
2. Silencer  - Adds a silencer to your gun if it can.
3. Cube Barricade  - A 1x1 barricade, having the length of a PCade and a height of a Normal Cade. This is so you can see in the cracks inbetween the walls and the barricade like the PCade, while still having the ability to look above it. (Not sure on cost.
4. Pack-a-Punch [1000-2000] - Paps any bo1 gun. Some guns will take more money IE m1911 will cost 2000.
4.5. Zombie Shield  - You have to have limb protector, and it must be charged, but then this adds a one extra hit per purchase. If limb pro is broken, you cannot buy this. Only if have you have a charged limb pro can you purchase this. (Sorry for saying that twice I just wanted to make it clear :D)
The 4.5. is backup for 4. in case you didn't like that idea.