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

Special order item - may require extra time to fulfill and ship. Special order parts are non-returnable.

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SKU: SO-21188
Regular price $35.99
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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.