The card is not an actual debit card linked to a personal bank account, but a prepaid card linked to the Square Cash app, according to Recode, and owners of the card can spend money that is available within a Square Cash account.
Dorsey tweeted an image in April, showing a customized signature on the front of his card.
A Square spokesperson told Recode that customers will be able to use their own signatures, which will be screened before printing to ensure that inappropriate words and drawings don't make it onto the final product. But it appears users will get to play around with their signatures, as evidenced by Dorsey's version, which includes an "@" sign — a nod to the other company he founded, Twitter.
The introduction of the physical cards appears to be Square's latest move to compete with rivals like Venmo and Apple Pay. Last year, the company introduced virtual prepaid debit cards that allows users to purchase items on websites and apps using funds from a Square Cash account.