What are price bands?

The exchanges have fixed price bands for all t securities within which they can move within a day i.e +-20%. In case of scrips on which derivatives products are available there is a price freeze of +/-20%.Orders outside the minimum and the maximum of the range are not allowed to be entered into the system. However in case of few specific scrips, from time to time the exchange has fixed price band of less than +/-20%.The previous day's closing price is taken as the base price for calculating the price bands.In case a member wants to execute a trade beyond +/-20% freeze (derivative scrips) then he will have to request the exchange to relax the price freeze for his particular order.