What is rebalance band?

Can someone describe this please?

Rebalance bands are essentially predetermined thresholds that dictate when portfolio rebalancing should occur. They help maintain the desired asset allocation within a portfolio by signaling when adjustments need to be made. Rebalance bands provide a range, often expressed as a percentage, within which you can tolerate the allocation shifting before taking action.

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If the asset allocation of the stock falls outside the rebalance band, the weights will be rebalanced back to the target value.