(1) Immeasurable love, (2) immeasurable compassion, (3) immeasurable joy and (4) immeasurable equanimity. Because they are developed in common by Hinayana and Mahayana practitioners, then although their audience is an immeasurable number of limited beings (sentient beings), they do not include arhats. Their actual attainment requires their being held by one of the states of mental constancy (Skt. dhyāna).
Tibetan: ཚད་མེད་བཞི། tshad-med bzhi