This specifies the burst size for the single rate two color mode. The unit is Kbytes. That is to say, 1 means 1kbytes. The set value range is 0..N, the value N is determined by project. A value of -1 indicates that this object is not active. This parameter is an optional parameter. The default value is 4kbytes.
Sources for this description
D-Link official switch MIBsD-Link MIB copies (LibreNMS/Observium Community)