12" Diameter | 5-Blade Fan | 25° Pitch | CCW Rotation | 5/16" Bore | NBK-21188

NBK-21188 – 12" Diameter | 5-Blade Fan | 25° Pitch | CCW Rotation | 5/16" Bore | OEM Replacement for Acme 31215 The NBK-21188 Fan Blade is a high-performance 12-inch replacement fan designed for HVAC and industrial ventilation systems. With its 5-blade configuration, 25° pitch, and counterclockwise (CCW) rotation, this fan blade ensures efficient airflow and reduced vibration. It serves as a direct OEM-equivalent replacement for Acme part number 31215 and includes a 5/16" bore for secure motor shaft mounting. Key Features: Precision Design – 5-blade, 25° pitch configuration for balanced airflow and optimal performance CCW Rotation – Counterclockwise operation compatible with standard ventilation motors OEM Replacement – Directly replaces Acme part #31215 Standard Shaft Fit – 5/16" bore for common motor shaft sizes Specifications: SKU: 21188 Category: HVAC / Fan Blades Diameter: 12" Blade Count: 5 Pitch: 25° Rotation: Counterclockwise (CCW) Bore Size: 5/16" OEM Brand: Acme Replaces OEM Part: 31215 Equivalent To: Acme: 31215 Why Choose the NBK-21188? The NBK-21188 is an ideal solution for replacing worn or damaged fan blades in HVAC and ventilation systems. Its balanced design and precise pitch ensure efficient airflow, reduced noise, and long-term reliability for both residential and industrial applications. Shipping & Availability: Special order from NBK. Please allow 1–2 business days for processing.