The contract size for rice is 2000 quintals (~ 91 tons) and the tick size at $ 0.005 per hundredweight ($ 10.00 per contract). The contract months are January, March, May, July, September and November. The last trading day is the business day before the 15th day of the delivery month. The electronic trading hours are 19:00 to 07:45 (at night) and 08:30 to 13:15 after Chicago time. More information can be found here.
The CBoT (Chicago Board of Trade) is one the oldest financial and commodity futures exchange based in Chicago. In 2007, the CME (Chicago Mercantile Exchange) and CBOT merged to share CME Group Inc.. At the CBOT both e-commerce and via "Open Outcry" is traded on the floor. You can find an overview of agricultural commodity futures here.