Enables calcium ion binding activity and protein homodimerization activity. Involved in several processes, including cochlea development; positive regulation of axon regeneration; and positive regulation of retinal ganglion cell axon guidance. Located in several cellular components, including cuticular plate; extracellular space; and stereocilium. Part of protein-containing complex. Orthologous to several human genes including OCM2 (oncomodulin 2). [provided by Alliance of Genome Resources, Apr 2022]