Adding Custom Tokens to MetaMask
In Meter, both MTR and MTRG are native network coins. However, Metamask can only display one native coin (ETH in Ethereum's case). We configured the gas token MTR to replace the default ETH in the wallet.
To properly display and transact MTRG, we created ERC-20 wrappers for MTRG and MTR so MetaMask and dApps could treat them as ERC-20 tokens as well.
MTRG can be treated as a custom ERC20 token in Metamask:
ERC20 System Interface: