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0.3 Amp Slo Blo Fuse MDL-3-10 - Bubbles Supply

0.3 Amp Slo Blo Fuse MDL-3-10

Part #: MDL-3-10

$3.86
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1-year warrantySame-day ship before 3pm CTPerfect Fit Guarantee30-day returns

About this fuse

The Allied Innovations 0.3 Amp Slo Blo Fuse MDL-3-10 is a critical electrical protection component designed for spa and hot tub control systems. This slow-blow fuse provides reliable circuit protection for low-amperage electrical components in your spa's control panel, preventing damage from minor power fluctuations while allowing normal startup surges to pass through safely.

Built to MDL specifications with a 0.3 amp rating, this OEM-quality fuse ensures your spa's sensitive electronics remain protected from electrical overload. At Bubbles Supply, we guarantee an exact fit for your system and ship the same day for minimal downtime. Every fuse comes backed by our comprehensive 1-year warranty for complete peace of mind. Always replace blown fuses with the exact same amperage rating and consult your spa's electrical diagram before installation to ensure proper circuit protection.

Exact part number

MDL-3-10

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Also known as / Replaces

This part replaces or is interchangeable with:

  • 0.3A slow blow fuse
  • 300mA slo-blo fuse
  • MDL 3/10 fuse
  • MDL-3/10

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

Technical specifications

Amperage
0.3A

Common symptoms this part fixes

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

  • Spa control panel is completely dead
  • Specific low-voltage circuit has no power
  • Ozone generator or transformer-fed accessory not functioning
  • Control board throws no output on a protected circuit
  • Spa shuts down intermittently under minor load fluctuation

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

Before you buy — quick checklist

  • Pull the blown fuse and confirm the rating stamped on the end cap reads 0.3A — never upsize a fuse to fix a repeated blow
  • Confirm MDL designation (glass tubular, 5x20mm format) matches your existing fuse physically
  • Inspect the fuse holder for heat damage or corrosion before installing a new fuse — a damaged holder will blow the replacement
  • Identify why the original fuse blew before replacing; a fuse that blows again immediately indicates a downstream short or overload that must be resolved first
  • Check your spa's wiring diagram to confirm this fuse's circuit location and protected component

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

Install difficulty: Easy — DIY-friendlyTypically 5-10 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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