The C9 indicator consists of a set of numbers (from 1 to 9) & the letter 'C'. The numbers & the letter 'C' are displayed on price charts at specific locations.
When a series of C9 numbers from 1 to 9 appear below prices, selling may be getting exhausted. When a series of C9 numbers from 1 to 9 appear above prices, buying may be getting tired.