A cardholder makes a $25 transaction at a gas pump. This is the same transaction shown in <a href="doc:card-transaction-examples#five-step-sequence" target="_blank">Five-step sequence</a> in _Card Transaction Examples_, except that these examples show Mastercard instead of Visa. Also see <a href="page:scenario-2-preauthorization-with-completion" target="_blank">Scenario 2: Preauthorization with Completion</a>.
In <<glossary:Production>>, most gas pump transactions arrive at Galileo over interbank (PIN) rails. However, the simulator only simulates Visa credit or Mastercard credit rails.
### Preauthorization
Call <a href="ref:post_createsimulatedcardauth" target="_blank">Create Simulated Card Authorization</a> with these parameters:
| Parameter | Value |
`accountNo` | <<glossary:PAN>> or <<glossary:PRN>> |
`amount` | `1` if you have upcharges configured for MCC 5542 or `75` if you do not |
`association` | `visa` or `mc_auth` |
`merchantName` | `Central Gasoline` |
`mcc` | `5542` |
`transType` | `2` |
Capture the `auth_id` for later use.
#### View the preauthorization
Call <a href="ref:post_getauthhistory" target="_blank">Get Authorization History</a> to see the preauthorization.
### Completion
Call <a href="ref:post_createsimulatedcardauth" target="_blank">Create Simulated Card Authorization</a> with these parameters to simulate the completion, because a completion comes to Galileo through the authorization stream.
| Parameter | Value |
`accountNo` | PAN or PRN |
`amount` | `25` |
`association` | `visa` or `mc_auth` |
`mcc` | `5542` |
`originalAuthId` | `auth_id` from previous response |
`transType` | `4` (Visa) or `3` (Mastercard) |
Capture the `auth_id` for later use.
#### View the Completion
Call <a href="ref:post_getauthhistory" target="_blank">Get Authorization History</a> to see the completion. Notice that the preauthorization is no longer present. It has been replaced by this completion, which has a new `auth_id`, and 25 is the new hold amount. When you settle the transaction, you settle this completion. The `original_auth_id` field contains the `auth_id` from the preauthorization.
### Settlement
Call <a href="ref:post_createsimulatedcardsettle" target="_blank">Create Simulated Card Settlement</a> with these parameters:
| Parameter | Value |
`authId` | `auth_id` from the completion response |
`accountNo` | PAN or PRN |
`association` | `visa` or `mc_auth` |
`amount` | `25` or leave blank |
### Transactions created
Call <a href="ref:post_getalltranshistory" target="_blank">Get All Transaction History</a> to see the five ledger entries, in reverse chronological order.