T2‐relaxation under‐spin‐tagging (TRUST) is a robust spin tagging based method to quantify oxygen extraction fraction (OEF), but it lacks spatial specificity. Recently O’Brien et al. proposed a method involving multiple saturation pulses to achieve spatial specificity. Parallel transmission (pTx) provides additional degrees of freedom for spatial localisation. A pTx RF pulse design strategy based on a shells trajectory is applied to perform regional OEF measurement at 7 T. Initial in-vivo results acquired from one healthy subject showed that spatial localisation of OEF could be achieved.