A fenestrated stent graft with a tubular side arm extending there from in which the side arm can be turned inside out to extend into the stent graft during deployment of the stent graft and extended out during deployment. Also disclosed is a deployment device for such a side arm stent graft which has a deployment catheter and a side arm guide, the side arm guide is releasably fastened at a proximal end to the branch tube and is able to be moved independently of the deployment catheter such that the branch tube can be extended from the tubular body of the stent graft while it is fastened onto the side arm guide. The side arm guide can be formed from a side arm catheter and a side arm guide wire carried in the side arm catheter.