What exactly leaves Polygon as WBTC?
WBTC is a contract representation on Polygon with 8 decimals at 0x1BFD67037B42Cf73acF2047067bd4F2C47D9BfD6. POL, not WBTC, pays gas unless both symbols are the same. A Polygon PoS source uses its validator/checkpoint system and POL gas; its token contracts and checkpoints are separate from Ethereum L1. WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer.
What exactly arrives on Ethereum as WETH?
WETH is a contract representation on Ethereum with 18 decimals at 0xb1A7F8b3AdA1Cbd7752c1306725b07D2F8B4e726. ETH, not WETH, pays gas unless both symbols are the same. 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. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.
Why does the WBTC to WETH direction matter?
WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer. On receipt, WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.
What changes between the source and destination asset roles?
WBTC is the deposited wrapped-asset input; WETH is the quoted token output. Source allowance or native-spend rules and destination wallet/representation checks are evaluated separately.
What should be matched before sending WBTC?
WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer. A Polygon PoS source uses its validator/checkpoint system and POL gas; its token contracts and checkpoints are separate from Ethereum L1. 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. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.
Can the wrapped asset pay native network gas?
No. WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer. A Polygon PoS source uses its validator/checkpoint system and POL gas; its token contracts and checkpoints are separate from Ethereum L1. 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.
What funds the Polygon source transaction?
POL is the native gas asset for Polygon. A Polygon PoS source uses its validator/checkpoint system and POL gas; its token contracts and checkpoints are separate from Ethereum L1. WBTC is token-tracked and can need approval before transfer.
Can I swap WBTC on Polygon to WETH on Ethereum without KYC?
Requirements are checked for the live WBTC Polygon to WETH Ethereum quote. Verification requirements can depend on the provider, amount, jurisdiction, and current route. Sasquatch does not verify this route as universally no-KYC; check the live flow before continuing.