Type CH clutches are designed specifically for heavy duty clutch and brake applications, and can be air or hydraulically actuated. The friction disc packs are suitable for either wet or dry operation. Actuation is accomplished through internal shaft and clutch passages. When used as a wet clutch, coolant oil may be applied as a splash or spray or forced through the friction disc pack from an internal shaft passage. The clutch hub is bored and keyseated for shaft mounting. Torque is transferred from the disc pack to a splined drive ring.