Pentair #8 External Tooth Lockwasher OEM | U43-21SSZ

Pentair #8 External Tooth Lockwasher OEM Pump Hardware | U43-21SSZ

OEM Pentair U43-21SSZ #8 external tooth lockwasher. Prevents loosening from vibration in Max-E-Pro, IntelliPro, and Dura-Glas pumps.

Features

• OEM Pentair replacement for secure fastening performance.
• External tooth design locks screws in place under vibration.
• Corrosion-resistant stainless steel for long service life.

Description

The Pentair U43-21SSZ External Tooth Lockwasher (#8) is a genuine OEM fastening component designed to keep critical pump hardware secure under constant vibration. Its external tooth (star) design grips the mating surface, preventing screws from backing out and protecting internal pump assemblies from loosening over time.

Built from corrosion-resistant stainless steel, this washer is engineered for long-term durability in harsh pool environments. It is commonly used across a wide range of Pentair and Sta-Rite pumps, including Max-E-Pro, IntelliPro, Dura-Glas, and Dyna series models.

This small but essential component plays a key role in maintaining pump stability, reducing vibration-related wear, and ensuring safe, reliable operation.

Pro Tip

When replacing pump screws or servicing the diffuser or seal plate, always install a new lockwasher—reusing worn washers can lead to loosening and premature failures.

Installation Tips

Disconnect power before servicing. Replace washers during reassembly to ensure proper locking. Do not overtighten fasteners to avoid damaging components.

We want you to have quick and easy access to warranty information for all the brands we carry. Please click on the links below to view each manufacturer’s warranty page:

• Pentair Warranty
  
• A&A (Pentair In-Floor) Warranty
  
• Fluidra Warranty (Zodiac / Jandy / Polaris / Caretaker)
  
• Paramount Warranty
  
• BlueSquare Warranty
  
• Hayward Warranty
  
• All Other Manufacturer Warranties
  

Note: Warranty coverage, registration, and service terms are provided directly by the manufacturer. Please review the details carefully to ensure proper understanding of coverage and claim procedures.