The Muncie Esna zinc nut, part number 3/8-16UNC-3B or 3816UNC3B, is a genuine Muncie hardware fastener used in PTO assemblies. The 3/8-16UNC-3B designation identifies the thread specification: 3/8-inch nominal diameter, 16 threads per inch, Unified National Coarse thread series, with a Class 3B internal thread tolerance for a close-fitting, precise engagement. The Esna design incorporates a prevailing-torque locking feature to resist loosening under vibration, which is a practical requirement in power takeoff installations. Pro Gear and Transmission supplies this part directly. Call us to confirm proper fitment for your specific PTO unit.
Features
Muncie Esna prevailing-torque locking nut for PTO hardware applications
3/8-inch nominal diameter, 16 threads per inch, Unified National Coarse (UNC) thread form
Class 3B internal thread tolerance for precise, close-tolerance fastener engagement
Zinc finish provides corrosion protection in underhood and drivetrain environments
Designed to resist loosening under vibration common in PTO installations
Sold by Pro Gear and Transmission as a genuine Muncie part
Tech Specs
- Thread Size: 3/8 inch nominal diameter
- Thread Pitch: 16 threads per inch
- Thread Series: Unified National Coarse (UNC)
- Thread Class: 3B (internal thread, close tolerance)
- Finish: Zinc
- Type: Esna prevailing-torque locking nut
