Membrane receptor that binds the K-D-E-L sequence motif in the C-terminal part of endoplasmic reticulum resident proteins and maintains their localization in that compartment by participating to their vesicle-mediated recycling back from the Golgi (By similarity). Binding is pH dependent, and is optimal at pH 5-5.4 (By similarity). Localized in the Golgi in the absence of bound proteins with the sequence motif K-D-E-L. Trafficks back to the endoplasmic reticulum together with cargo proteins containing the sequence motif K-D-E-L. Binds the C-terminal sequence motif K-D-E-L in a hydrophilic cavity between the transmembrane domains. This triggers a conformation change that exposes a Lys-rich patch on the cytosolic surface of the protein (By similarity). This patch mediates recycling from the Golgi to the endoplasmic reticulum, probably via COPI vesicles (By similarity). Belongs to the ERD2 family.