Norgren 4255-51 Frl Regular Knob Acetal Plastic

Product Description

The NORGREN 4255-51 is an acetal plastic regular knob designed for use with compact compressed air filter units in FRL (filter-regulator-lubricator) assemblies. This replacement knob allows technicians to manually adjust or remove the filter bowl on compatible compact-style air preparation components. Acetal plastic construction provides resistance to moisture and common shop chemicals while keeping weight low at 0.2 pounds. At 1.48 inches in height, the knob provides a practical grip surface for hand-tightening in tight panel or manifold installations. It is installed by maintenance technicians, pneumatic system specialists, and industrial service professionals.

This knob is suited for compressed air filter servicing in industrial, commercial, and light manufacturing environments where FRL assemblies regulate and clean air supply lines. Typical applications include pneumatic control panels, production machinery air preparation systems, and facility air distribution stations. It is used wherever a compact compressed air filter requires a standard manual-adjust or bowl-removal knob as a service or replacement part.

Key Features

• Acetal plastic construction resists moisture and common industrial chemicals
• Compatible with compact compressed air filter units in FRL assemblies
• 1.48 inches in height for comfortable hand grip during bowl servicing
• Lightweight at 0.2 pounds for easy handling in overhead or confined installations
• Sold as a single-piece replacement accessory

Compatibility

Designed for use with compact compressed air filters in NORGREN FRL assemblies. Verify fitment against the specific filter model before ordering, as knob attachment styles may vary across FRL product families.

Installation Notes

This knob is installed by qualified pneumatic system technicians or maintenance personnel. Before servicing, depressurize the compressed air line completely and verify that downstream equipment is isolated. Hand-tighten only — do not use tools that may crack or stress the acetal plastic knob body. Follow applicable facility lockout/tagout procedures before removing or replacing any FRL component.