> For the complete documentation index, see [llms.txt](https://docs.chamberfi.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.chamberfi.com/ecosystem/flat-money.md).

# Flat Money

Flat Money is a Chamber sibling brand. In its current form (v2), it's a **perpetual options contract layer** on Arbitrum that [Toros](/ecosystem/toros-finance.md) uses as the underlying mechanism for its options strategies.

There's no standalone end-user front-end right now. Flat Money sits as infrastructure; depositors interact with it indirectly by holding Toros options tokens.

## Status

* **v1: deprecated.** The original Flat Money product (flatcoin / UNIT) is wound down.
* **v2: live.** Perpetual options contracts on Arbitrum, used internally by Toros. The standalone product direction is in flux.

This page will be rewritten if and when a direct end-user product ships.

## Relationship to Chamber

Same team, same treasury, same [10% DAO fee split](/treasury-and-protocol-economics/dao-protocol-fees.md) on anything that earns fees through the stack. See [Ecosystem overview](/ecosystem/overview.md) for how the sibling brands fit together.