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Drain Plug Adapter 672-4350 - Bubbles Supply

Drain Plug Adapter 672-4350

Part #: 672-4350

$7.67
In stock — ships today
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🔒 Secure checkout↩️ 30-day returns✅ 1-year warranty
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1-year warrantySame-day ship before 3pm CTPerfect Fit Guarantee30-day returns

About this union/fitting

The Waterway 672-4350 Drain Plug Adapter is a precision-engineered plumbing component designed for spa and hot tub drain systems. This OEM replacement part features 1/4" male pipe thread (MPT) to 3/8" raised body (RB) connections with a convenient 3/8" hex head for easy installation and removal.

Built to Waterway's exact specifications, this drain plug adapter ensures reliable sealing and proper drainage functionality. The threaded design provides secure attachment while the hex head allows for proper torque application during installation. At Bubbles Supply, we guarantee this adapter will deliver an exact fit for your spa, backed by our comprehensive 1-year warranty and same-day shipping on in-stock orders. Always verify thread specifications and connection types before installation to ensure proper fit with your existing drain assembly.

Exact part number

672-4350

Save this for ordering or warranty claims

Also known as / Replaces

This part replaces or is interchangeable with:

  • drain plug adapter
  • hot tub drain plug fitting
  • MPT to RB adapter
  • spa drain fitting

Looking for an older part number? Check our supersession lookup tool

Common symptoms this part fixes

If your spa is showing any of these signs, this part is likely your fix:

  • Slow or incomplete spa drainage
  • Drain plug leaking at the fitting connection
  • Stripped or cross-threaded drain plug seat
  • Cracked or broken drain plug adapter
  • Water seeping from drain assembly at rest

Not sure if this is your problem? Try our diagnostic centre or .

Before you buy — quick checklist

  • Confirm your existing drain fitting uses 1/4" MPT male pipe thread on the spa-side connection
  • Verify the drain assembly accepts a 3/8" raised body (RB) connection
  • Inspect the existing adapter for thread damage — if the seat is stripped, this adapter alone may not resolve the leak
  • Confirm the 3/8" hex head is compatible with your access space and available tools
  • Check whether an O-ring or sealant is required at your specific drain port — this adapter does not include thread sealant

Reading the checklist now prevents 90% of returns. Worth the 60 seconds.

Install difficulty: Easy — DIY-friendlyTypically 15–30 minutes

Warranty

1 year manufacturer warranty against defects

Covers manufacturing defects. Does not cover improper installation, normal wear, or accidental damage.

Warranty claims: warranty@bubblessupply.com

Perfect Fit Guarantee

Ordered with our help and the part doesn't fit? Contact us before installation. We'll resolve it with an exchange, replacement recommendation, or return approval.

Learn about our Perfect Fit Guarantee →

Shipping

We ship across the US and Canada. US orders ship from our US warehouse to US customers; Canadian orders ship from our Canadian warehouse to Canadian customers — no cross-border shipping, no surprise duties. In-stock orders placed before 3pm CT ship same day. Standard shipping $9.95 flat rate. Free shipping on orders over $200. Express options available at checkout.

Returns

30-day hassle-free returns on unused parts in original packaging. Contact us before returning to receive your RMA number.

Frequently asked questions

Check the Compatibility section above to confirm fitment for your spa brand and model. If your model is not listed, use our fitment selector at /pages/find-my-part or ask our parts AI for a personalized recommendation.

In-stock orders placed before 3pm CT ship the same day. You will receive tracking information by email as soon as your order ships.

We accept returns within 30 days of delivery for unused items in original packaging. Email returns@bubblessupply.com with your order number to start a return. Installed electrical parts cannot be returned for safety reasons.

Yes, all new parts come with a 1-year warranty against manufacturing defects. Warranty does not cover damage from improper installation or normal wear and tear.

Customer reviews

AI Fitment Assistant

Tell us your spa model and we will confirm this part fits before you buy.

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