What is "krachappi"

The krachappi , also spelled grajabpi, is a plucked, fretted lute of Thailand, used in central Thai classical music. It is made jackfruit or teak wood, and it has four strings in two courses that are plucked with a plectrum. It usually has a long decorative wooden "tail." It is one of the oldest Thai classical instruments and has been little used since the 20th century.