Amazon offers the Cooler Master 120mm Silent Case Fan 4-in-1 Value Pack, model no. R4-S2S-124K-GP, for $10.99 with free shipping. That's the lowest total price we could find by $2 and a very low price for such a Cooler Master fan without rebate hassles. It runs at 1,200 rpm and features air flow of nearly 45 cfm, 19.1dB noise level, and more.