Which blockchain do we use?

We are deployed on the Polygon blockchain. This blockchain is a Proof-of-Stake protocol. Proof-of-Stake comes with a number of improvements to the Proof-of-Work system:

  • Greener – Polygon’s validators consume approximately 0.00079TWh of electricity every year, far from the energy consumption by the major PoW blockchain networks (35 to 140 TWh).

  • Faster - In terms of transaction speed, Polygon can handle up to 65,000 transactions per second on a single side chain, with a block confirmation time of fewer than 2 seconds.

  • Cheaper - Polygon solves the problems associated with blockchains, such as high transaction fees ("gas fees") and slow speeds, without sacrificing security.

  • Stronger – Proof-of-stake leads to more nodes in the network and consequently less risks.

The Polygon Network is based on Ethereum standards. This way, all tokens & NFTs created through Bolero Music respect the ERC-20 & ERC-721 standards.

What are gas fees on Bolero Music?

To validate any transactions on the blockchain, the network needs resources. Of course, this is not free and it corresponds to the famous "gas fees" linked to the blockchain.

Because we are based on Polygon network, you only need to buy 1 $MATIC to make thousands of transactions.

What are the recurring actions where you need to pay gas fees on Bolero:

  • Buying artist’s token
  • Buying NFT
  • Selling your NFT
  • Accepting an offer
  • Cancelling a bid

How do I found my transaction hash?

Transaction hash is an identifier used to uniquely identify a particular transaction. All on-chain transactions have a unique transaction hash that can be found in transaction details.

This is an example of a transaction has:


On Metamask, you can check all your activity directly on by searching your wallet address. Or you can directly open your extension, click on the 3 dots and then on “View Account on explorer”.

metamask hash

How to change network on Metamask?

This question is for users who are connected with the wrong network, or if you have any issues with the network "chainstacklab" of Polygon.

Step 1:

Click on the Metamask extension, then on the network you are currently connected to. (Ethereum on the sreenshot). It will open all networks available.

If you don't have "Polygon Mainnet" avaibale, click on "add network" and go to step 3 directly.

If you have trouble with your actual Polygon Mainnet network, you need first to change the network from Polygon to Ethereum. This will allow you to delete the Polygon network. Then click on "Add Network".

metamask network

Step 2:

On the left side, click on "Network". If you already have the Polygon Mainnet with the url "chainstacklab", you can delete it. If you are still connected to this network, you won't be able to delete it, change your current network to "Ethereum".


Step 3:

Click on "Add a network". Then you need to fill some information to add the right "Polygon Mainnet" network:

  • Network name: Polygon Mainnet
  • New RPC URL:
  • Chain ID: 137
  • Currency symbol: MATIC
  • Block Explorer URL:

Click on "save".

metmask networkmetamask network

Finally, back to your Bolero account, on the Metamask extension, check that the network is "Polygon Network"! Congrats, you can now invest in tokens and NFTs securely!