Hayward DEX2421J2 Clamp Nut & Bolt Kit (Replacement Hardware for Filter Clamp Ring)

The Hayward DEX2421J2 is an OEM clamp nut and bolt kit used to tighten and secure the clamp band that holds the upper and lower tank halves together on compatible Hayward filters. If your clamp hardware is rusted, stripped, missing, or won’t tighten smoothly, replacing this nut/bolt set helps restore a secure, leak-resistant clamp connection.

Fits / Compatibility

• Hayward SwimClear cartridge filters (commonly listed across multiple SwimClear models depending on revision)
• Hayward Pro-Grid vertical grid D.E. filters: DE2420, DE3620, DE4820, DE6020, DE7220
• Also commonly referenced for certain Hayward clamp systems used on select sand filter configurations (verify by parts diagram)

What It Does

• Provides the tightening bolt and nut used to tension the filter’s clamp ring
• Helps maintain even clamp pressure so the tank seal can seat properly
• Restores clamp function after corrosion, thread damage, or missing hardware

What’s Included

• (1) Clamp bolt
• (1) Clamp nut

Note: This kit is the bolt and nut only. If you need the full clamp system (clamp ring + seal + hardware), look for the complete clamp kit for your filter model.

Installation Notes

• Turn off the pump and fully relieve filter pressure at the air relief before loosening/tightening the clamp.
• Clean the clamp band and tank flange area—grit can cause uneven clamping and leaks.
• Tighten smoothly and evenly per the filter manufacturer’s instructions (do not overtighten).
• If the seam still seeps, inspect/replace the tank seal and check for flange damage or warping.

Related Products

• Hayward DEX2421J2 Clamp Nut & Bolt (search)
• Hayward DEX2421JKIT Complete Clamp System Kit (search)
• Hayward Metal-Reinforced Tank Seal (search)
• Hayward Pro-Grid DE4820 Parts (search)
• Hayward SwimClear C4030 Parts (search)
• Silicone O-Ring & Gasket Lubricant (search)

Maintenance Tips

• Never work on a filter clamp while the system is pressurized—always shut the pump off and bleed air first.
• Inspect clamp hardware each time you open the filter; replace any stretched, corroded, or damaged fasteners early.
• Keep the tank seal clean and lightly lubricated with silicone-based lube to improve resealing and reduce pinching.
• If you repeatedly need to overtighten to stop seepage, replace the tank seal and inspect flange surfaces instead of forcing the clamp.