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Smith-Cooper 1/8 in. FPT X 1/8 in. D Stainless Steel Union

Meet the Smith-Cooper 1/8 in. FPT X 1/8 in. D Stainless Steel Union β€” a compact, corrosion-resistant connector designed to join two small-diameter lines with a clean, leak-tight se…

Smith-Cooper MPN 4638102600 In Stock & Ready to Ship
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About Product Overview

Meet the Smith-Cooper 1/8 in. FPT X 1/8 in. D Stainless Steel Union β€” a compact, corrosion-resistant connector designed to join two small-diameter lines with a clean, leak-tight seal. Crafted from durable stainless steel and built to be lead-free, this union delivers reliable performance in water, air, and light industrial applications where space is at a premium.

  • Two 1/8" connections: one end features a 1/8" Female Pipe Thread (FPT), while the opposite end provides a 1/8" diameter connection for a tight, space-saving join.
  • Alloy that lasts: stainless steel construction resists rust, corrosion, and harsh environments, making it ideal for outdoor irrigation, workshop lines, and equipment feeds.
  • Precision and reliability: manufactured for accurate threading and a compact profile, so you can install in confined spaces without compromising seal integrity.
  • Removable, maintenance-friendly: the union design allows quick assembly and disassembly, enabling easy maintenance, reconfiguration, or repairs without soldering or permanent fittings.
  • Lead-free safety: formulated to meet modern safety standards, suitable for potable water and standard fluid systems where code compliance matters.
  • Protected during storage: bagged packaging helps prevent contamination and ensures clean, ready-to-use threads upon arrival.

How this fitting solves real-world problems

In tight installations where space and material compatibility are critical, this Smith-Cooper union provides a robust connection without bulk. Whether you’re routing small-diameter water lines, supplying pneumatic circuits, or linking instrumentation ports, the 1/8 in. FPT X 1/8 in. D union keeps your system flowing smoothly and reconfigurable for future needs.

Who benefits most

  • Professional plumbers, HVAC technicians, and irrigation specialists who value corrosion resistance and dependable seals in compact fittings.
  • Engineers and technicians assembling small-diameter networks in laboratories, workshops, or field sites.
  • DIYers working on projects where a removable, metal-to-metal seal is preferred over soldered joints.

Installation and care tips

  • Prepare mating surfaces by cleanly removing debris and ensuring threads are undamaged before assembly.
  • Use a compatible thread sealant or PTFE tape rated for your fluid type and system pressure, applying sparingly to prevent contamination.
  • Tighten gradually with appropriate tools to achieve a snug seal without over-tightening, then check for leaks after pressurizing the system.
  • Periodically inspect the union in service, especially in environments with vibrational loads or thermal cycling.

The Details Specifications

Brand Smith-Cooper
SKU 4890018
UPC 092201427410
Unit 0
Case Pack Quantity 5 per case
Retail Unit Quantity 1
Unit of Measure 0 0
Dimensions (L × W × H) 1 × 4 × 4
Weight 0 lbs
Cubic Feet 0.00618 ft³
Country of Origin VIETNAM
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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