Tag:OER(hSTIM1) consists of the luminal and transmembrane domains (amino acids 1-250) of the human STIM1 gene (HGNC:11386), in which the EF-SAM domain (amino acids 58-201) has been deleted. When fused to the N-terminal end of a gene of interest, Tag:OER(hSTIM1) results in the tagged protein being anchored to the outer endoplasmic reticulum membrane, with the tagged protein localized on the cytosolic side (PMID:27616195).