What is "Schedule of Rate"

Schedule of Rates is a document containing different items and their respective unit rate. It's like a Bills of Quantity (BQ) wihtout the "quantity" colomn.
Schedule of Rates is usually use in contract without quantities and Term maintenance contract. The contractor will be asked to insert their bidding price for each item which will then be used as the basis for assessing variations. And for Term maintenance contract, quantity of works will be measured after completion & multiply by the unit rates in the Schedule of Rates to arrive at the cost.