In Zen monasteries, a wooden board struck by the fukudo with a mallet announcing sunrise, sunset and the end of the day. At AZC, it is used to summon participants to the zendo for daily zazen. The pattern of strikes always includes three roll downs: the first ending with one strike, the second with two, and the third with three. The han is sounded every 50 seconds between each roll-down. Practitioners are expected to be in the zendo and settled in their seats by the second roll-down, as the Doshi and Jiko enter the zendo as a procession at the third roll-down.