WBTC input identity and handling
Wrapped Bitcoin is classified as a wrapped asset for this route. WBTC uses a wrapped contract asset on Arbitrum. The recorded Arbitrum representation uses 8 decimal places. WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer.
Leaving Arbitrum L2 for Ethereum L1
Arbitrum inclusion and its ethereum settlement are distinct from final receipt on Ethereum. The live route, rather than a generic rollup withdrawal assumption, determines the provider path and timing for this direction.
WBTC unwrap or exchange input check
WBTC is a custodial tokenized Bitcoin representation on smart-contract networks. Its transfers use token contracts and approvals rather than native Bitcoin inputs and outputs. On this route WBTC is the source token on Arbitrum. Its token balance, approvals, and contract transfer behavior are separate from the native coin used for network gas.
Ethereum destination execution
Ethereum is a L1 EVM network in the Ethereum ecosystem. ETH pays destination-side network gas on Ethereum. EVM 0x account address An Ethereum receipt is an L1 native ETH balance or ERC-20 contract event; later token movement can require ETH gas and a new approval for another contract.
ETH output identity and receiving
Ethereum is classified as a native asset for this route. ETH uses a native asset on Ethereum. The recorded Ethereum representation uses 18 decimal places. Determine whether ETH arrives as native destination gas or as a tokenized representation. Only the native balance can directly pay that network’s fees.
Arbitrum source execution
Arbitrum is a L2 EVM network in the Ethereum ecosystem. ETH pays source-side network gas on Arbitrum. EVM 0x account address On an Arbitrum source, the Nitro sequencer records L2 execution before Ethereum settlement completes; ETH funds gas and ERC-20 inputs can need approval.
EVM-to-EVM execution boundary
Arbitrum and Ethereum 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 WBTC Arbitrum to ETH Ethereum
Route-specific mistakes include sending on a network other than Arbitrum; using a destination that is not valid for Ethereum; running out of ETH before the source transaction is submitted; treating a wrapped token as the native gas asset. On an Arbitrum source, the Nitro sequencer records L2 execution before Ethereum settlement completes; ETH funds gas and ERC-20 inputs can need approval. WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer. An Ethereum receipt is an L1 native ETH balance or ERC-20 contract event; later token movement can require ETH gas and a new approval for another contract. Determine whether ETH arrives as native destination gas or as a tokenized representation. Only the native balance can directly pay that network’s fees.