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Danco 3/8 in. D Rubber Slip Joint Cone Washer

Danco 3/8 in. D Rubber Slip Joint Cone Washer

Seal every connection with confidence using the Danco 3/8 in. D Rubber Slip Joint Cone Washer. Designed for universal slip-joint applications, this compact rubber cone washer deliv…

Danco MPN 38834B In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $1.99. Our online price is $1.99.
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Case of 5 · List Price $9.95
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About Product Overview

Seal every connection with confidence using the Danco 3/8 in. D Rubber Slip Joint Cone Washer. Designed for universal slip-joint applications, this compact rubber cone washer delivers dependable performance where a tight seal matters most.

Constructed from durable rubber, it compresses to fill gaps and irregularities in the seal surface, helping prevent leaks at common connections in under-sink and plumbing lines. The red color makes it easy to identify at a glance during repairs or kit inventories.

  • Interior diameter: 3/8 in
  • Exterior diameter: 5/8 in
  • Thickness: 0.38 in
  • Material: Rubber
  • Finish/Color: Red
  • Fit: Universal slip joint compatibility
  • Packaging: 1 washer per polybag

Ideal use cases

  • Replacements in sink supply lines and faucet connections where the cone washer has worn or deformed
  • Repairs to toilet supply fittings or other household slip-joint assemblies
  • Emergency kit component for DIY plumbing projects to stop slow leaks before they become drips

Why choose rubber cone washers for slip joints? The cone shape concentrates compression where the nut tightens, creating a more reliable seal than flat washers in many slip-joint scenarios. Rubber’s elasticity accommodates small alignment differences, resists water exposure, and remains flexible over temperature changes, reducing the risk of leaks as the system settles.

Installation tips

  • Ensure the mating surfaces are clean and free of debris before reassembly
  • Place the Danco slip-joint cone washer in the correct orientation before tightening the slip nut
  • Hand-tighten, then snug with a wrench just until the seal stops leaks — avoid over-tightening which can crush the washer
  • Run water and observe for leaks; replace if any seepage is detected

The Details Specifications

Brand Danco
SKU 4209557
UPC 037155388349
Unit 0
Case Pack Quantity 100 per case
Retail Unit Quantity 5
Unit of Measure 0 0
Dimensions (L × W × H) 6 × 3 × 1
Weight 0 lbs
Cubic Feet 0.00223 ft³
Country of Origin CHINA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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