Fi 3+ Behavior Adapter
Keep the gear your dog loves. Add a compatible Fi tracker.
Adapter only — Fi tracker and collar or harness are not included.
Shipping & exchanges
Made to order. Approximate ship date: within 3 weeks, often sooner. Carrier transit time is additional. Shipping details
Estimate shipping in your cart before checkout. Final shipping and taxes are confirmed at checkout.
No change-of-mind returns. Eligible unused U.S. exchanges have a $35 fee, including return and replacement shipping; email authorization is required within 30 days of delivery. Exchange eligibility and exceptions
PRODUCT DETAILS
What to know before ordering
Collar placement designed for GPS + behavior tracking.
Fits Fi 3+ · Collar only. Keep your dog’s current collar while positioning the Fi 3+ module to hang freely from its endlinks at the neck, as required by this adapter’s behavior-tracking setup.
Choose this adapter when Fi 3+ behavior insights matter to you alongside location tracking. For a compact mount on a collar or harness, choose the Fi Compact Adapter.
What is behavior tracking?
Fi’s behavior insights show patterns such as barking, eating, drinking, licking, and scratching. The Fi device and app record these insights; this adapter provides the collar placement designed to support them. Correct fit and placement matter.
Fit and compatibility
For Fi 3+ on a compatible collar only. For Fi Series 2, Series 3, or harness use, choose the Fi Compact Adapter. Identify your Fi model if you’re unsure.
Match your collar’s strap width, then select your snap style and hardware finish. Available width choices are ¾ inch, 1 inch, 1½ inch, 2 inch, and Other for a width noted at checkout.
Handcrafted in Alaska with durable polyester webbing and marine-grade hardware.
FI ADAPTER
Let’s finish your adapter setup.
We already know which Fi family brought you here. Now match the adapter to the gear it will attach to, the strap width, and the hardware you prefer.
Where will this adapter be used?
Behavior Adapter is a collar-only path so the Fi 3+ module can sit in the intended neck position.
Measure the strap where the adapter will sit. Choose the corresponding published adapter option.
Choose the available snap hardware for this adapter.
YOUR ADAPTER
Fi 3+ Behavior Adapter
- Dog
- Fi
- Placement
- Strap width
- Hardware
WHY A MARTINGALE?
Secure when needed. Relaxed when it isn’t.
A martingale is a limited-slip collar. It sits relaxed during normal wear and reduces its opening when leash tension is applied, helping prevent a dog from backing out of the collar.
The standard EDG martingale is built without a buckle, so it must pass over the widest part of the head and then adjust at the neck. If you add the Tactical Buckle, the collar opens instead and neck measurement drives the size.
The goal is secure, properly fitted movement—not continuous pressure.