At the core of the cylinder, as the axle of the wheel, is a "life tree" made of wood or metal with mantras written on or wrapped around it.
A long strip of rolled-up paper bearing printed or inscribed mantras rather than prayers, per se, is inside the cylinder.
[2] According to the Tibetan tradition, the prayer wheel lineage traces back to the famous Indian master, Nagarjuna.
In Buddhism, Buddhas and Bodhisattvas have created a variety of skillful means (upaya) to help bring practitioners ever closer to realizing enlightenment.
On rare occasions, advanced Tantric practitioners such as those of Senge Dongma, the Lion-Faced Dakini, spin prayer wheels counterclockwise to manifest a more wrathful protective energy.
Not only does it help wisdom, compassion and bodhichitta arise in the practitioner, it also enhances siddhis (spiritual powers such as clairvoyance, precognition, reading others thoughts, etc.
Thubten Zopa Rinpoche has commented that installing a prayer wheel has the capacity to completely transform a place, which becomes "...peaceful, pleasant, and conducive to the mind."
The cylinder itself is affixed with a cord or chain terminating in a small weight allowing it to be spun by a slight rotation of the wrist.
The weighted chain, known as a “governor” in Western technology, stabilizes the wheel and keeps it spinning with less input from the practitioner than would otherwise be the case.
The cylinders of fixed prayer wheels are often inscribed with the formula “Om mani padme hum” (meaning “jewel in the lotus”) in ornamental Lantsa (Ranjana) letters.
The water that is touched by the wheel is said to become blessed and carries its purifying power into all life forms in the oceans and lakes that it feeds into.
[citation needed] Electricity can certainly be considered similar to the above sources of energy for PW (water, fire, wind).
The Lamas and practitioners who build, maintain and pay for the electricity rightly help to generate and dedicate the merit.