After releasing the revolutionary Air Penetrator AP181 fan that contributes to making the RAVEN and Fortress series the best cooling case on the market, SilverStone has released the updated 180mm Air Penetrator Fan AP183. Updated with an improvement in IC and motor design, the AP183 exceeds AP181 in every aspect. It has a maximum speed of 1,500 rpm (vs. 1,200 rpm) while still consuming only 3.6 W (vs. 5.4 W). With silent operation, AP183 rotations can be reduced to 400 rpm, and it is virtually impossible to hear noise, but AP181 can be up to 500 rpm even when the voltage is lowered. For convenient and accurate control of fan rotations, AP183 introduces PWM and allows users to utilize a wide range of rotational speeds. Dual ball bearings are added to accommodate higher RPM AP183 for increased durability during extended high performance applications.