the cash and the futures are exactly the same instrument used for trading the alsi.
Only difference why one is called cash and other futures :
1. interest and dividend is included in the futures contract for the 3 months until futures closeout. So when u buy a futures contract, u dont pay or receive interest daily as cost is included in. In case of cash u will pay/receive interest daily .
2. cash tracks the underlying of the top 40 shares while alsi tracks the underline plus interst/divi
3. cash contract with ig who is unregulated is about R7000.00 margin while futures contract with a regulated broker is about R30000.00
forgot to add that if you want to use IG and not futures to trade, use it for day trading only....IE during the day it tracks the underlying....after hours the thieves can spike it either way big..If so you may wake up in the morning when a drained out account...