The Number has had a limited amount of the vests made and has donated them to the charity, which will sell them for £5 each.
The Number chief executive Chris Moss said the company decided to make the limited-edition shirts in response to demand from the public.
"Since we launched our advertising campaign, the 118 vest has become extremely recognisable, to the point where it has cult status. We have had hundreds of calls from the public asking for vests and we are pleased customers can now get hold of theirs on the high street for the first time," he said.
All proceeds will go to Cancer Research UK and the shirts will be available in 400 shops across the country.
Juilia Russell, donated product marketing manager at the charity, called the shirts a "must-have" for the summer. "I only hope we have enough stock for the demand," she said.
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