Specific lists of objects vary somewhat among the different schools and sects. Here are the most important ritual devices of the Celestial Masters school. First and foremost are the ubiquitous talismans that consist of a written magical formula or mantra symbolizing a contract between the deities and human beings engaging in a ritual exchange. Only a qualified ritual specialist may execute a talisman, which usually includes a specially drawn Chinese character as well as other visual symbols appropriate to a particular spiritual purpose. Possessors of talismans generally think of them as guarantees of divine aid. People wear them or hang them in home or office to attract positive energies. The “Precious Sword of the Seven Stars,” symbolizing the Big Dipper, appears often in blessings and exorcisms, whether for individuals or as part of Cosmic Renewal observances. As a symbolic purification to the cardinal directions, ritualists sip from a copper bowl and blow a spray through closed lips. Stone seals of various kinds allow the specialist to make official documents such as talismans. Priests hold a stiff tablet, as if reading from a book. In exorcism rituals, Black Hats use the sword along with handbells, while Red Turbans use a horn and a whip.