GRACO Jam Nut - (SKU: 16U977) The GRACO 16U478 is a

The GRACO 16U478 is a right-side bracket and frame component designed for use in GRACO equipment

but it is engineered to regulate and reduce system pressure

Inspect cover and mixer element for wear or damage before installation

specifically for upper piston block assemblies

3900 Series / M12 x 1

GRACO Jam Nut - (SKU: 16U977) The GRACO 16U478 is aThe GRACO 16U977 is a jam nut, typically made from metal, designed to secure and lock components in place within GRACO pump assemblies. Its primary function is to prevent loosening of threaded connections under vibration or pressure, ensuring reliable operation of GRACO equipment. Key Features: Jam Nut 16U977 Compatible with select GRACO pump assemblies (e. g., 680cc Pump Lower) Secures threaded connections Prevents loosening under vibration or