Enables fibronectin binding activity and insulin-like growth factor binding activity. Involved in several processes, including female pregnancy; lung alveolus development; and negative regulation of skeletal muscle hypertrophy. Acts upstream of or within several processes, including hair follicle morphogenesis; negative regulation of osteoblast differentiation; and regulation of insulin-like growth factor receptor signaling pathway. Predicted to be located in extracellular region. Predicted to be part of insulin-like growth factor ternary complex. Predicted to be active in extracellular space. Is expressed in several structures, including central nervous system; embryo ectoderm; impulse conducting system; limb; and metanephros. Orthologous to human IGFBP5 (insulin like growth factor binding protein 5). [provided by Alliance of Genome Resources, Apr 2022]