How it works: this option defines the volume amount of the cluster, at which it will be completely colored. Cluster - is a level that displays the number of triggered traded contracts.
Example: you have set a value at 300. If at some price the buying and selling volume amount will be filled by 150 contracts, therefore, the cluster will be filled by half. if the amount of buying triggered orders is greater than the amount of selling orders, the cluster will be colored in green. Otherwise, the cluster will be colored in red.