mUSDC, or Monstro USDC, is an ERC-4626 vault token on Base that represents USDC deposited into the Monstro USDC vault. The vault is designed to provide a productive form of USDC, where each mUSDC share is backed by USDC held by the vault and the exchange rate can increase over time as fees and protocol revenue enter the vault. mUSDC is used across the Monstro ecosystem, including as the productive stablecoin layer for Based Loans, allowing idle USDC liquidity to remain useful while still maintaining simple USDC-denominated accounting.