You can use this in two ways, with or without the standard cast iron charcoal grate fitted in position. Generally you would remove the charcoal grate and fit this basket instead.
Designed to maximise airflow around the charcoal, and prevent loss of temperature over long cooks because there is no grate to get blocked up with ash.
As with all KJ accessories, this is beautiful quality and designed to last, with 5mm thick bars on the sides, 8mm bars in the divider and 10mm in the base! Flexible cook rack is additional.