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All About Our Fi Series 3 Compatible BioThane Collars

What is a Fi Unit? 

Fi is a company that makes GPS tracking units you can attach to your dog’s collar or harness. These units allow you to track the location of your dog in real time.  Fi is tuned into 78 GPS satellites to locate your dog within a 6 foot radius. 

High Tail Hikes’ newest BioThane collars are made to be compatible with Fi’s newest Series 3 tracking units.

Fi collars can also keep you keep track of and monitor your dog’s well being – including their steps, activity level, and sleep patterns.

How can I use the Fi collar with my dog?

When your dog is wearing a Fi collar you’ll have peace of mind that you’ll be able to locate your dog if they get lost. A Fi unit is also a great way to track your dog’s activity and sleep patterns. 

If your dog goes out with a dog walker, you’ll know when they got picked up and dropped off, where they went, and how much activity they got! 

A Fi unit is NOT a shock collar - there is not tone, vibrate, beep, or shock function on any Fi unit. 

How long is the battery life on a Fi unit?

Fi collars are extremely power-efficient. The Fi Series 3 can last up to 3 months on a one-time charge. You can charge your Fi collar’s battery without removing the Fi unit from the collar itself. 

Are Fi collars waterproof?

All of our Fi Series 3 compatible collars are waterproof. Fi units have been tested at being submerged in 1.5 m of water for 30 minutes, as well as with high-pressure water jets. So your water loving dog can wear a Fi collar and you can have peace of mind!

How do I get the Fi Unit on and off of my dog’s collar?

There is a small magnetic tab that keeps the Fi unit securely in place while your dog is wearing it. To take it on or off, open the magnetic tab, rotate the unit 90 degrees, slide the unit in our out of the slot, and then flip the magnetic tab closed.

Dog wearing a Fi collar

What size Fi collar should I choose? 

Please size your dog properly for their collar before placing an order. There are two ways to size your dog for a collar:

  1. Use one of your dog’s existing collars to determine their measurement. Lay the collar down flat on a tape measure or cutting mat and measure the distance from where the two points of the collar meet when the collar is being worn.

  2. Use a length of string or a soft cable (like a phone charging cable) to measure around your dog’s neck where a collar would naturally sit. Allow enough space for 2 fingers to fit underneath the collar to ensure that the collar will not be too tight. Transfer the string or cable to a cutting mat or tape measure and check the measurement. Measure several times to ensure you have an accurate measurement. 

Please also watch this video where we review how to size your dog for a collar.

Your dog’s neck measurement should ideally fit in the middle of the sizing range of the collar that you choose. Due to the Fi Unit and hardware being built into the collar, our Fi collar sizing may be different from our standard collar sizing. Do not order a Fi collar if you are unsure of your dog’s neck measurement. Please contact us for assistance. We are always happy to help, or to make your collar in a custom size by request. 

Because these collars integrate third party hardware, and because of the degree of customization involved, we cannot offer returns or exchanges on Fi Compatible Collars for any reason unless we made a mistake, no exceptions.

What options do you offer for the collars? 

High Tail Hikes’ Fi Series 3 Compatible BioThane Collars are available in Sport and Classic Brass styles, in Layered or Integrated Designs, and in 16+ colors, allowing you to design a one of a kind collar that matches your dog's personality and style!

Fi Series 3 BioThane Collar - Brass Integrated Design

Fi Series 3 BioThane Collar - Sport Integrated Design

Fi Series 3 BioThane Collar - Brass Layered Design

Fi Series 3 BioThane Collar - Sport Layered Design


What’s the difference between the Layered and Integrated Designs? 

With the Layered Design, the Fi Unit sits on top of the collar band. With the Integrated Design, the unit is "built in" to the collar, so the unit itself will sit on your dog's neck. Both designs have been tested for strength and durability. For the layered design, you will choose a collor for the main collar band, and you can choose another color for the end link accents. For the Integrated collar, you can choose either a single color or a two tone design ($8).

What’s the difference between the standard and two tone options for the Integrated Design? 

Our two tone design includes alternating colors on either side of the unit. It just adds a splash of color and allows you to personalize the design a bit more! There is no functional difference between the single color and two tone option.

For the Integrated design, do I have to worry about my dog breaking the unit by pulling on the collar? 

All of our Fi collar styles have been tested for strength and durability. The Fi unit itself has a full stainless steel body frame that can sustain 400 lbs of force. You can rest assured that your unit will remain safely connected to your dog's collar! That said, we always recommend a non restrictive harness if your dog has the tendency to pull on leash. 

Do you sell Fi collars for small dogs? 

We do offer our Fi compatible collars in size Small (9-12”) in both brass designs, but unfortunately, due to more hardware being integrated into the collar and the lack of adjustability, we can only make the Sport Collars to fit a neck size of 13” and up.

How do I clean my Fi Collar?

All of our BioThane Collars are waterproof, stink proof and are so easy to clean. We recommend rinsing your gear after a trip to the beach or a muddy walk to prevent salt and grime from wearing down your hardware prematurely. To clean your gear, you can soak in mild soapy water, scrub gently with a towel or toothbrush, rinse, and towel dry. Basic maintenance of your BioThane gear will ensure your dog gear lasts longer.

Is the collar compatible with my Series 1 or Series 2 unit?

These collars are not compatible with the Series 1 or Series 2 units. If you do have a Series 1 or Series 2 unit, and would like for us to build a collar for you - contact us and we may be able to help! 

Does the collar come with the Fi unit?

Collars do not include the Fi Smart Dog Activity Tracker unit. The unit must be purchased separately through Fi at When you purchase your unit through Fi, you will set up an account and activate your unit. Use code HIGHTAILHIKES20 to get $20 off your activation fee when you purchase a unit!

Why are these collars more expensive than your other collars? 

Our Fi compatible collars integrate third party hardware (end links) from Fi that increase our costs. Additionally, these collars take more time to construct due to the precision sizing and placement of the end links. We have worked hard to price these collars accessibly while still accounting for the additional time and components involved.

More questions? Contact us anytime!