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K9 Advantix II Large Dogs 21-55 lbs Flea & Tick Treatment – 6 Doses

K9 Advantix II Large Dogs 21-55 lbs Flea & Tick Treatment – 6 Doses

Regular price $55.40
Regular price Sale price $55.40
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Shipping & Returns

Free USA Shipping on Orders Over $120

We ship all US domestic orders within 1-3 business days

Returns & Refunds Policy

30-Day Return Policy

We offer a 30-day return policy from the date of delivery.

To qualify for a return:


  • The item must be unused

  • The item must be in original packaging

  • Proof of purchase is required

Non-Returnable Items

The following items cannot be returned:


  • Opened pet food or treats

  • Personalized products

  • Clearance or final sale items

  • Hygiene-related pet products

Damaged or Incorrect Items

If you receive a damaged or incorrect product:


  1. Contact us within 72 hours of delivery

  2. Provide photos of the product and packaging

  3. We will arrange a replacement or full refund

Return Shipping


  • If the return is due to our error (damaged or incorrect item), we cover return shipping

  • If the return is due to customer preference, the customer pays return shipping

Refund Processing

Once we receive and inspect the returned item:


  • Refunds will be issued to the original payment method

  • Processing time: 5–10 business days
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Keeping your dog protected from fleas and ticks is important for their comfort and overall health. K9 Advantix II for Large Dogs is specially made for dogs weighing between 21–55 lbs, offering reliable monthly protection against fleas, ticks, mosquitoes, lice, and biting flies.

This easy-to-use topical treatment works quickly to kill fleas and repel pests before they bite. Whether your dog enjoys daily walks, outdoor play, or spending time in the yard, K9 Advantix II helps keep them protected throughout the month. The waterproof formula continues working even after bathing or swimming once fully absorbed.

Unlike ordinary flea treatments, K9 Advantix II not only kills parasites but also helps stop them from bothering your dog in the first place. With regular monthly use, it helps reduce flea infestations and supports a healthier environment for your pet and home.

Key Features

  • Fast-acting flea and tick protection
  • Repels fleas, ticks, and mosquitoes before they bite
  • Protects for up to 30 days
  • Waterproof formula after 24 hours
  • Easy monthly topical application
  • Suitable for dogs weighing 21–55 lbs
  • Helps control flea infestations and irritation

Why Pet Owners Choose K9 Advantix II

Many pet owners trust K9 Advantix II because it provides strong, long-lasting protection without complicated treatments. It is simple to apply and works well for active dogs that spend time outdoors. The formula starts working quickly, helping your dog stay comfortable and protected from harmful pests year-round.

How to Use

Apply the full contents of the tube directly to your dog’s skin between the shoulder blades. Use once every 30 days for continuous protection. Always read the label instructions carefully before use.

Frequently Asked Questions

1-Is K9 Advantix II safe for large dogs?

Yes, K9 Advantix II is designed for dogs weighing between 21–55 lbs and puppies older than 7 weeks.

2-How long does K9 Advantix II last?

Each application provides up to 30 days of protection against fleas, ticks, and other biting insects.

3-Does K9 Advantix II kill ticks?

Yes, it helps kill and repel ticks, reducing the risk of tick bites and related health problems.

4-Can my dog swim after applying K9 Advantix II?

Yes, the treatment becomes waterproof after 24 hours, so it continues working even after swimming or bathing.

5-How fast does K9 Advantix II work?

The formula starts killing fleas within 12 hours and continues protecting your dog throughout the month.

6-Can I use K9 Advantix II on cats?

No, this product is made for dogs only and should never be used on cats.