The UND is a stablecoin that is pegged to USD and collateralized by LPT (Liquidity Pool Tokens). The value of UND minted is based on the value of the deposited LPT. The amount of UND minted at the time the LPT was deposited is the amount that the user must pay back in order to get their original LPT. Minted UND will be burned once deposited in the Unlock contract before the original collateral is returned to the user. Arbitrageurs in AMM pools ensure that the Dollar peg is maintained.