Robinhood Markets, the company behind the popular mobile application known for commission-free equity trades, is introducing free cryptocurrency trading with a coupe of catches.

First, only bitcoin and ethereum will be able commission-free for Robinhood users. Second, the deal is only open to clients in four states – California, Massachusetts, Missouri and Montana.

“Robinhood Financial has rolled out commission-free trading for bitcoin and Ethereum across California, Massachusetts, Missouri and Montana, the company said on Twitter. As CCN previously reported, users will still be responsible for fees charged by the underlying exchanges. But you can’t beat the quick access to funds,” reports CCN.

Related: 3 Steps to Responsible Bitcoin Investing

What is Robinhood?

Robinhood introduced commission-free stock trades three years ago and has since added options and exchange traded funds to its platform. The company introduced trading in bitcoin and ethereum in February. When the company introduced crypto trading, it was unveiled to clients in just five states.

“Robinhood Markets, the company behind the popular stock trading app of the same name, is set to receive a capital injection valuing it at around $5.6 billion,” CNBC reported last month, citing the Wall Street Journal.