Walmart offers the Holmes Dual Blade Twin Window Fan for $19.88. (Amazon charges a few cents more.) Opt for in-store pickup to dodge the $5.99 shipping fee. That's tied with our mention from three weeks ago and the lowest price we could find now by $15. It features twin 6" blades, adjustable extender screen, extender panel, replaceable 5-amp fuse, and two speed settings.