Supply to SEZ treated as inter State supply, enabling zero rate treatment and refund subject to authorised receipt endorsement. Services of short term accommodation, conferencing and banqueting supplied to a SEZ developer or unit are to be treated as inter State supply. Supplies to a SEZ qualify as zero rated supplies only when received by the SEZ for authorised operations with an endorsement by the specified officer, and suppliers may claim refund of unutilized input tax credit or integrated tax paid subject to procedure. Fabric processors performing job work services remain eligible for inverted duty refunds because their output is a service, not goods.