> For the complete documentation index, see [llms.txt](https://docs.stacks.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stacks.co/cookbook/stacks.js/cryptography-and-security/build-an-ft-pc.md).

# Build an ft pc

{% code fullWidth="false" expandable="true" %}

```typescript
import { Pc, PostConditionMode } from '@stacks/transactions';

// Create a post-condition for fungible token transfers
const postCondition = Pc.principal("ST1PQHQKV0RJXZFY1DGX8MNSNYVE3VGZJSRTPGZGM")
  .willSendGte(500) // Amount in token's smallest unit
  .ft("ST1HTBVD3JG9C05J7HBJTHGR0GGW7KXW28M5JS8QE.token-ft", "my-token");

// Use in transaction options
const txOptions = {
  // ... other transaction options
  postConditions: [postCondition],
  postConditionMode: PostConditionMode.Deny,
};
```

{% endcode %}

### Description

Create post-conditions for fungible token transfers to ensure exact amounts are transferred as expected

### Use Cases

* Securing fungible token transfers with amount validation
* Protecting users from unexpected token transfers in DeFi protocols
* Ensuring token swaps happen with expected amounts

### Key Concepts

* `.ft()` - Takes two parameters: contract address with asset name and token name as defined in the contract
* The `Pc` builder for fungible tokens provides a fluent interface for creating post-conditions


---

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