ETH input identity and handling
Ethereum is classified as a native asset for this route. ETH uses a native asset on Base. The recorded Base representation uses 18 decimal places. Native ETH can fund both transfer value and gas on its selected network. If the source is WETH or another tokenized form, approval and unwrap or exchange logic differ.
Base to Optimism L2 handoff
This route crosses two L2 execution environments. Base settles to ethereum, while Optimism settles to ethereum; each side keeps its own gas balance, token contracts, transaction hash, and settlement progress.
WETH wrapped-token output check
WETH is a contract wrapper for ETH. It can be transferred as a token but cannot replace the native gas balance required by the network. On this route WETH is the destination token on Optimism. Its token balance, approvals, and contract transfer behavior are separate from the native coin used for network gas.
Optimism destination execution
Optimism is a L2 EVM network in the Ethereum ecosystem. ETH pays destination-side network gas on Optimism. EVM 0x account address An OP Mainnet receipt belongs to the OP Stack L2 and needs ETH on that network for later activity; it is not an Ethereum L1 balance.
WETH output identity and receiving
WETH is classified as a wrapped asset for this route. WETH uses a wrapped contract asset on Optimism. The recorded Optimism representation uses 18 decimal places. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.
Base source execution
Base is a L2 EVM network in the Ethereum ecosystem. ETH pays source-side network gas on Base. EVM 0x account address A Base source transaction is sequenced on the OP Stack rollup and later settles to Ethereum; Base ETH and Base token approvals remain on the L2 ledger.
EVM-to-EVM execution boundary
Base and Optimism can use the same 0x address syntax, but they are separate networks with different chain identifiers, gas balances, token contracts, and transaction histories. The recorded settlement context includes ethereum, so L1 and L2 confirmation behavior should not be assumed identical.
Mistakes specific to ETH Base to WETH Optimism
Route-specific mistakes include sending on a network other than Base; using a destination that is not valid for Optimism; running out of ETH before the source transaction is submitted; treating a wrapped token as the native gas asset. A Base source transaction is sequenced on the OP Stack rollup and later settles to Ethereum; Base ETH and Base token approvals remain on the L2 ledger. Native ETH can fund both transfer value and gas on its selected network. If the source is WETH or another tokenized form, approval and unwrap or exchange logic differ. An OP Mainnet receipt belongs to the OP Stack L2 and needs ETH on that network for later activity; it is not an Ethereum L1 balance. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.