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Anvil 3/8 in. FPT Galvanized Malleable Iron Lock Nut

Anvil 3/8 in. FPT Galvanized Malleable Iron Lock Nut

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

Meet the Anvil 3/8 in. FPT Galvanized Malleable Iron Lock Nut — a purpose-built securing solution for 3/8" female pipe thread fittings. Crafted from durable malleable iron and fini…

Anvil MPN 8700162459 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $6.99. Our online price is $7.99.
$7.99
Includes free shipping on orders over $75 · $8.99 standard below
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You might find it for less locally. Independent retailers often offer competitive pricing — some products are even cheaper in-store than online.
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About Product Overview

Meet the Anvil 3/8 in. FPT Galvanized Malleable Iron Lock Nut — a purpose-built securing solution for 3/8" female pipe thread fittings. Crafted from durable malleable iron and finished with a rugged galvanized coating, this lock nut is designed to stand up to moisture, temperature changes, and everyday use in both residential and light industrial piping applications.

  • 3/8" FPT compatibility: Precisely sized for standard female pipe threads, delivering a reliable, leak-resistant connection where it matters most.
  • Galvanized finish: Provides corrosion resistance in damp, outdoor, or humid environments, extending the life of your fittings without sacrificing performance.
  • Malleable iron construction: Combines strength with ductility to maintain a strong lock under vibration, pressure fluctuations, and repeated disassembly/reassembly.
  • Maximum pressure up to 150 psi: Suitable for typical residential and light commercial water lines and other low- to moderate-pressure piping systems.
  • Pro-grade reliability: Designed by Anvil to deliver consistent performance when securing fittings in everyday plumbing, irrigation, and light industrial setups.

Ideal use cases

  • Securing 3/8" FPT connections in water supply lines, irrigation hardware, and garden plumbing projects.
  • Replacing worn or corroded lock nuts in damp basements, crawl spaces, or outdoor installations where moisture is a factor.
  • Maintenance and repair tasks that require a dependable, reusable lock nut to keep fittings tight over time.

Installation tips

  • Ensure mating parts have compatible male threads; clean threads before assembly for a seal that lasts.
  • Use appropriate thread sealant tape or paste if your system requires it, and tighten to a secure fit without over-torquing.
  • After installation, perform a leak test to verify the connection and recheck periodically in environments with vibration or temperature cycling.

Choose the Anvil 3/8 in. FPT Galvanized Malleable Iron Lock Nut for a durable, corrosion-resistant, and reliable locking solution that keeps your fittings secure. It’s the practical, field-tested choice for real-world piping challenges.

The Details Specifications

Brand Anvil
SKU 46225
UPC 690291039119
Unit 0
Case Pack Quantity 25 per case
Retail Unit Quantity 1
Unit of Measure 0 0
Dimensions (L × W × H) 4 × 4 × 0
Weight 0 lbs
Cubic Feet 0.00782 ft³
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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