At the risk of derailing the discussion off Equitel and the thin SIM..... those with Dual SIM phones should be aware that both slots are often not 3G capable. There's usually a primary slot (usually SIM1 slot) that does 3G while the other one does 2G. Ensure that you slip the 'internet data' SIM card into the 3G slot.
Meanwhile Equitel Tweeted this yesterday :
"A thin SIM is costing Equitel Ksh 600. We are giving it for Ksh 500 and you get Ksh 200 worth of airtime at activation. #Equitel"