INTEL LGA 1851 & 1700 ONLY: Low-profile heat sink only used for Intel LGA 1851 & 1700, its a good ideal size for small form PC case. ARGB DUAL RING LIGHTING: Dual ring lighting effect can sync with motherboard via 5V 3-Pin interface to illuminate the build. PWM SMART CONTROL: 4-Pin PWM control allows for dynamic speed adjustment between 800-2500±10%RPM, Min noise or max airflow. UNIQUE AIRFLOW DESIGN: Top-to-bottom airflow can cooling the CPU first and hardware surrounding the motherboard. REMOVABLE DESIGN: The upper butterfly fan can be removed separately, which is convenient for you to clean.