What is the meaning round beads around the neck of Sha Wujing?

As a kid I enjoyed watching drama Journey to the West (1986),
>Wiki : Shā Wùjìng is one of the three disciples of the Buddhist pilgrim Xuanzang. He appears as a character in the novel Journey to the West written by Wu Cheng'en in the Ming dynasty, although versions of his character predate the Ming novel. In the novels, his background is the least developed of the pilgrims and he contributes the least to their efforts. He is called Sand or Sandy and is known as a "water buffalo" for his seemingly less developed intelligence in many English versions of the story. > >His Buddhist name "Sha Wujing", given by Bodhisattva Guanyin, means "sand aware of purity". His name is rendered in Korean as Sa Oh Jeong, into Japanese as Sa Gojō, into Sino-Vietnamese as Sa Ngộ Tịnh.
>He is also known as 沙僧 "Monk Sha", "Shā Sēng" in Mandarin Chinese, Sa Tăng in Sino-Vietnamese and Sua Cheng in Thai . I saw actor "**Sha Wujing **" necklace with huge, weighing up to 5kg.
I want to ask the meaning of this kind of necklace. ?
In Buddhism, Who had that necklace?