Mark Howard has played a couple of times for Arsenal reserves and also for the first team last summer in pre season.
He has been on loan at Falkirk and the Bairns were hoping to sign him as first choice keeper for next season but he has chosen to move to Wales.
"He is a young and ambitious player of high quality who has grown at Arsenal," owner Sam Hammam told the official website.
"He found it hard to break into the first team, but has benefited from learning his trade with some of the best players in the world.
"He has also had full match experience in the Scottish Premier League, playing their last eight games as first-choice keeper.
"He comes to us highly recommended and is the sort of player we are looking to bring in to improve our squad."
It's uncertain yet whether Martyn Margetson will return to the club as a goalkeeping coach.