How to Trade Up to USP-S | Serum
USP-S | Serum drops from CS:GO Weapon Case 2CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, CS:GO Weapon Case 2, so any contract that can produce it needs 10 Restricted skins from those same cases. Here is what the contract costs, what else it can land on, and the input float you need for each exterior.
- Odds per contract
- 50% 1 in 2
- Contract cost from
- $10050.00 10× cheapest input
- Expected value
- $5369.00 mean of the outcome pool
- Margin
- -46.6% $-4681.00 per contract
Buying is cheaper than rolling. A Field-Tested USP-S | Serum costs $5397.00 outright, against $10050.00 for a contract with a 50% chance of producing one. Trade up for the process, not the value.
The contract
Ten inputs, all Restricted, all from CS:GO Weapon Case 2CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2 or CS:GO Weapon Case 2. Concentrating every input in one case is what keeps your odds at 50% — mixing cases splits the probability across both pools and lowers your chance at USP-S | Serum specifically.
What else this contract can land on
A contract from CS:GO Weapon Case 2CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 / CS:GO Weapon Case 2 draws uniformly from every Classified Pistol skin in the pool, so USP-S | Serum is one of 2 equally likely results. These are the other 1.
| Outcome | Odds | Cheapest price |
|---|---|---|
| USP-S | Serumyour target | 50% | $5397.00 |
| P90 | Cold Blooded | 50% | $5341.00 |
Input float for each exterior
CS2 normalises float across a trade-up: each input’s float becomes a 0–1 position inside its own range, those are averaged, and the average is applied to USP-S | Serum’s range of 0.00–0.25. To land a given exterior, your ten inputs must average the normalised float below.
| Target exterior | Output float | Required avg. input float |
|---|---|---|
| Factory New | 0.0350 | 0.1400 |
| Minimal Wear | 0.1100 | 0.4400 |
| Field-Tested | 0.2000 | 0.8000 |
| Well-Worn | — | not reachable |
| Battle-Scarred | — | not reachable |
“Not reachable” means USP-S | Serum’s own float range never enters that exterior band — no combination of inputs can produce it.
What USP-S | Serum is worth right now
Worth comparing against the contract cost above before you commit: buying the skin outright is frequently cheaper than rolling for it.
| Exterior | Price | vs. contract cost |
|---|---|---|
| Field-Tested | $5397.00 | −$4653.00 |
| Minimal Wear | $6015.00 | −$4035.00 |
| Factory New | $11791.00 | +$1741.00 |
Build this contract
Price a full ten-slot contract against live inputs, set your own float values, and see the outcome odds update as you go.