The Sanskrit name for the White Umbrella Deity is Ushnisha Sitatapatra [Tib: dü kar] which can also be translated as "The Victorious White Parasol." Her parasol indicates her ability to protect sentient beings from natural catastrophes, diseases, and so forth. She is white in color, because the principal means by which she accomplishes this function is the enlightenment energy of pacification.
Ushnisha Sitatapatra is a female form of Avalokiteshvara, the Bodhisattva of Compassion. Like him in his elaborate form, she also has a thousand eyes that watch over living beings, and a thousand arms that protect and assist them. Thus she symbolizes the power of active compassion.
The mantra is:
OM SIT TA TA PA TREY HUM PHET
[Note: A White Umbrella Deity practice booklet is available from FPMT. The booklet is a collection of two practices, “The Supreme Accomplishment of Sitatapatra,” and “Praises and Repelling Practices of Sitatapatra.”]