Size - 3.6 x 3.6 Inches, Mounting hole spacing - 3.24 x 3.24 Inches. Featuring Noctua's AAO frame and sophisticated aerodynamic design measures such as Flow Acceleration Channels, the NF-A9x14 is a highly optimized, premium quality quiet fan in 92x14mm size. Due to its thickness of only 14mm, the NF-A9x14 is a perfect match for low profile CPU coolers and all other applications that require slimmer fans. Noctua's custom-designed PWM IC for fully automatic speed control and reference class SSO2 bearings guarantee superb running smoothness and excellent long-term stability. Topped off with modular cabling, a Low-Noise Adaptor and 6 years manufacturer's warranty, the NF-A9x14 is a premium choice for the highest demands.