Concentration of the fourth jhana of five (Buddhism)

With the elimination or fading away of rapture or happiness, two factors remain in the fourth jhana: ease or bliss; concentration.

According to Hinayana Buddhism, concentration is considered as of one kind (monad), of two kinds (dyads), of three kinds (triads), of four kinds (tetrads) or of five kinds (pentad). In the pentad, fivefold according to the five jhana factors, this is the fourth concentration. It is equivalent to the third concentration in the third tetrad.