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Smith-Cooper 3/8 in. FPT X 3/8 in. D FPT Stainless Steel Cap

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Meet the Smith-Cooper 3/8 in. FPT X 3/8 in. D FPT Stainless Steel Cap — a rugged, lead-free solution designed to seal dual 3/8" ports with precision and lasting reliability. Crafte…

Smith-Cooper MPN 4638100020 In Stock & Ready to Ship
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About Product Overview

Meet the Smith-Cooper 3/8 in. FPT X 3/8 in. D FPT Stainless Steel Cap — a rugged, lead-free solution designed to seal dual 3/8" ports with precision and lasting reliability. Crafted from corrosion-resistant stainless steel, this cap stands up to demanding environments, making it a smart choice for plumbing, hydraulic, and industrial applications where reliability matters.

Why this dual-end cap stands out

  • Dual 3/8" FPT ends provide streamlined closure for two ports with a single component, reducing part count and installation time.
  • Stainless steel construction delivers superior corrosion resistance and durability in demanding conditions, outperforming plated or softer metals over the life of the system.
  • Lead-free design supports safety and compliance in systems where lead content matters, including sensitive or potable-related environments, without sacrificing strength.
  • Service ratings include a maximum pressure of 300 psi and a maximum temperature of 300°F, making it suitable for a wide range of hydraulic, pneumatic, and general piping tasks.
  • Bagged packaging ensures clean storage and easy handling on busy job sites.
  • Standards-compatible fit designed to mate with standard 3/8" male pipe threads, offering straightforward integration into existing assemblies.

Practical uses and ideal applications

This cap is engineered for situations where two 3/8" ports must be safely sealed without a bulky assembly. Ideal buyers include maintenance technicians, field installers, OEM engineers, and DIY professionals working with hydraulic or plumbing lines. Use cases include:

  • Sealing unused or test ports on dual-port manifolds during commissioning or maintenance
  • Temporary closures in hydraulic and pneumatic test rigs
  • Maintenance-friendly port protection in equipment housed in humid or corrosive environments

Specifications at a glance

  • 3/8" FPT
  • 3/8" FPT
  • FPT
  • FPT
  • Stainless Steel
  • 300 psi
  • 300°F
  • Bagged
  • Cap
  • Lead-Free

Installation guidance and best practices

  • Ensure mating ports have clean, undamaged threads before installation.
  • Use appropriate sealant rated for stainless steel on male threads (e.g., PTFE tape or pipe thread sealant) to ensure a secure, leak-free seal.
  • Hand-tighten the cap onto each 3/8" male port, then apply a light final turn with a wrench. Avoid overtightening to prevent thread damage.
  • Inspect for leaks after initial system pressurization and re-tighten if necessary, following standard safety procedures.

The Smith-Cooper 3/8 in. FPT X 3/8 in. D FPT Stainless Steel Cap delivers dependable, dual-port sealing in a compact, corrosion-resistant package. Its lead-free composition, robust temperature and pressure ratings, and easy integration with standard 3/8" male threads make it a practical, long-lasting choice for professionals who demand precision and reliability from every connection.

The Details Specifications

Brand Smith-Cooper
SKU 4215208
UPC 092201425614
Unit 0
Case Pack Quantity 5 per case
Retail Unit Quantity 1
Unit of Measure 0 0
Dimensions (L × W × H) 1 × 2 × 4
Weight 0 lbs
Cubic Feet 0.01039 ft³
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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