Send ethereum tokens with zero gas price

Question

I have seen the following transaction:

https://etherscan.io/tx/0x173fd250d63a62bb407f214ff924b49e1c90593572eab1a8c523783f2aa58ba3

And I've seen that the gas price is 0. How could I do the same? When I use web3 it says that transaction is underpriced, however if this guy has sent tokens at gasPrice 0 it must be possible. I've seen that some pools do accept transactions with gas price 0.

Do you know how I could send the tokens without setting a gas price? Is there a specific client that may allow me to do this?

I am aware of the implications of not setting a gas price, the transaction may not get mined and such. I just want to know how this can be done.

Answer 1

As you said, zero gas price transactions are totally valid but might take a looong time (eternity?) to mine. It seems at least Mist allows zero gas price transactions: Can I set the gas price to whatever I want?

In theory any client could allow it, but probably it's not supported in some clients due to not making much sense.

Upon googling I also stumbled upon a partially relevant, but interesting rant about zero gas price txs: https://www.reddit.com/r/ethereum/comments/7lx1do/a_christmas_mystery_sweepers_and_zero_gas_price/

P.S. The tx you linked has other txs with the same nonce and at least some of them have gas price above zero. But difficult to say of course what the user has tried to accomplish.