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TrackPack Mounting System

thumb_Trackpack-logoThe backpack mounting method has been used in various ways by research biolgists for many years, with some better than others. Mark Williams of Alberta Canada refined the best basic design and proved its viability for falconry. This figure eight approach was further simplified and put in to production by Marshall Radio as the "TrackPack Mounting system" to add yet a fourth mounting method to choose from. In just seven years it has become a widely used mounting option by falconers all over the world. The TrackPack is the 'ready-to-go kit' for the backpack mounting method. Starting with a gently curved Mounting Plate machined from UV-protected Delrin plastic, we add 36 inches of small width Teflon tubular ribbon and a small brass crimping ring produced just for this purpose that's internally threaded for maximum bite into the ribbon when making the final setting.

Simply use either flat needle-nose pliers or your existing MRT Tail-piece crimping tool to set the ring in place once the harness is correctly fitted.

You can follow the installation process shown in our latest video here: English : Spanish

There are now three sizes: Regular size accomodates all transmitters, a Micro size for very small birds that fits only the Micro transmitter, and the new XL (Eagle) size with 18 more inches of ribbon.

Also available is the Re-Installation Kit, containing 36 inches of Teflon ribbon and the threaded crimping ring. Choose one of these items from the drop-down list after clicking on the 'add to cart' button below.

Key Features

Only Tubular Teflon Ribbon used

The material used for the actual harness is critical to the safety of the idea. Tubular ribbon has no edges to cut or injure, and is inherently slippery and smooth. This is the same material that has been selected and used for many years by the Peregrine Fund here in the US and around the world for the attachment of harnesses in their migration studies.

Smooth and slippery Delrin mounting plate

Leather_Plectrum_w-DelrinWe originally used a simple leather pad with an aluminum tail piece mounted to it for the mounting plate. What was learned is that the leather would, over time, develop a slight figure eight shape as the sides curled up through pressure between the shoulders during the upward wing strokes.

Two_Delrin_PlatesWe replaced leather with a similar shape piece of machined Delrin whose width was narrow and whose length just enough to attach the tail spring and protect from the bottom of the transmitter. Delrin is a high-strength machinable plastic and will not act as a heat sink or otherwise cause irritation in relation to temperature.

All edges are rounded and smooth, and the overall shape is gently curved to better match the shape of the back. We use an expensive UV-resistent Delrin that is rated for 20 years in direct sunlight without becoming brittle or cracking. So, it's possible your kids will inherit your used mounting plates.


Extra length of ribbon for sizing and extra fit

Starting with a length of 36 inches, or 18 inches per side, allows enough extra room on most Hawks and Falcons to have about 5-7 inches extra to use for manipulation, sizing decisions and general handling.


Custom internally threaded brass crimping ring



We take brass tubing and tap a thread into it to provide a better bite when it is crimped. It has been tested, by hanging a bucket with weights, to around 25 pounds of holding strength.




Three Sizes

The Micro size TrackPack uses the tightest smallest ribbon, and will only accomodate a Micro sized spring.

The Regular size TrackPack will accomodate all transmitters, including the Micro, although it will not be quite as snug.

The XL or Eagle size TrackPack uses the 1/4 inch ribbon and a longer mounting plate helps position the ribbon lower on the torso. This can be used for large Buteos as well.

Common Questions

Does it negatively affect the way a bird flies?

How dificult is it to install on a bird without using sedatives?

How do I know if it's fitting correctly?

How many people have tried this mounting method so far?

I have a friend who says it's dangerous. Have there been problems?

Can the bird get hung up on something?

How long can it be left on my bird?

How hard is it to remove at the end of the season or if the fit is wrong?


Customers Say

Howard_Brinkerhoff"I’ve been wanting to get all the junk off my bird’s feet for years now, even going so far as to have totally removable jesses, but I still had some issues with getting the tailmount to work for me.
It’s now happened with the TrackPack mounting method. I put it on my new female passage prairie in early January this year and fly it with just one of your ultra-reliable RT+'s. The bird is flown every day now and two months later I still haven't had the low battery indicator come on yet! I just love to entire setup.
To any skeptics out there, I say: ‘You need to try this before forming an opinion.’ I think it’s the future of how we’ll be mounting telemetry on our falconry birds in the years to come. It’s just so obvious once you start using it. Thank you Marshall!"
Howard Brinkerhoff


Ken_Tuttle"I have flown my Barbary about 5 days a week since June and have never seen him pay any attention to the harness or transmitter. I have never had such negligible effects from a telemetry system, and Al Ross feels the same way, even flying a PowerMax on his Merlins! My system only weighs ten grams total including the PowerMax, which you can just barely even see in this picture here.

"By the way, I just got back from a week of hawking with Harry McElroy. He flies every day, an Aplomado one day and a Harris’ the next. Both of these hawks crash the bush constantly. The desert mesquite has thorns and is wicked. I came out bleeding every day, but his hawks have never hung up with this system. We discussed this at night and he agreed that this is now the best system!"
Ken Tuttle



"My 320 gram Aplomado carries about 10 1/2 grams of harness including the 7 gram PowerMax and in the process overtakes a share of mourning dove. The dove is not a slow creature. I estimate that she travels about 20 % faster than quail that she is chasing and that too would indicate good speed using the harness.

In the field the Aplomado flew right past my left shoulder and I thought how she was free of anything that I could see. Her tail was in perfect form too."
Harry McElroy





"Nicky, my tiercel Peales, killed a Hun on his 1st flight the next morning with his new backpack you installed for me at the Canadian Meet."
Dave Knutson






"I must admit, it feels like guilty pleasure just putting on one transmitter each time out in the field, having the PowerMax on the tail and the new RT+ on the back, and then just tapping them with the magnet to turn on the two transmitters right before the flight. I just leave the RT+ on 24/7. No fight, no fuss, no bitten fingers right before the flight."

Tim Jessell




"Unfortunately I won't be able to do a long-term test on the backpack as my bird was killed by a chicken farmer. The best thing about the backpack was the ease of putting on and taking off the transmitter. Most birds do not like the tail mounts, well maybe not the tail mounts but the process of putting them on and taking them off. The worry with the fit was certainly eased by watching another bird be fitted, the hands on is the best way to go. Perhaps you could do a little video about it. The more people that have seen it done and can pass on the correct way to do it the better. You coming to the Canadian meet and going to the NAFA and CHC meet will spread the good word.

"I can't wait to get another bird to put my backpack to good use."
Roy Priest




"I now use a backpack on both passage Merlins and it’s just great. These are birds that are flown every day and catching game. Even the smallest transmitters are an nuisance and hinderance when leg mounted on these tiny birds. Being up on the back out of the way to keep the feet free is such a great improvement. I recommend it to everybody."

Al Ross




"I really like mine. It’s been a good idea."

Joseph Terry (a man of few words, but when he does actually speak, everyone stops and listens)






"I really think this is one of the best leaps forward in terms of finding a new and safer method for putting and keeping transmitters on our birds.

"I now use it on both my Merlin and the big bird."

Steve Schwartz




"I really think this will come to be another one of those innovations that we can't live without. I love my experience with it, especially this year.

"Last year my anatum's harness didn't fit quite right and she fought it. But this year, no problems, and I feel much safer with it. Skeptics just need to see it done and in use like everyone else did at the Canadian meet. Thanks again for helping so many get started. You made a lot of New Believers."
Burt Loessberg





"The backpack has worked fantastically....

"It completely disappeared into her plumage the next morning after she bathed. And she flies like it doesn't exist."

Ralph Rogers



Mark_Williams"I hear some say that they’d never consider it because they’ve heard of the mortality experienced by some researchers who used harnesses with the large GPS transmitters. I can say that I don't think any falconer who uses it does so knowing he is hurting or effecting his bird in some negative way or other. Yes, fit is important but just because some early research designs might have been poorly made and fitted is no reason to judge the current style adapted for falconry. A bit like comparing the risks of the early airplane designs with those of today.

"I started pursuing this because I cared about my bird and wanted to find an alternative to leg mounting. I have now used this for nearly 3 seasons and will never go back!"
Mark Williams



"I have a little cassini tiercel that’s on the wing all day long on sort of a 'tame hack.' He comes in at the end of the day and is put inside for the night. He’s just catching starlings and caching them in different places like a wild bird. I have a BackPack Harness on him and it’s just no problem. He is totally fit and flies around here like it not even there. It's really something."
Ricardo Velarde


Ken_Riddle"Thanks for developing the backpack harness and for sending the newest version. I love it. It fits well and seems to provide an easier platform for removing the transmitter. Both my tiercels finished the duck season with 32 and 35 respectivley. The RT+ was left on the one bird the entire time without consequence. The other bird was re-transmittered every day without incident. I will leave both backpacks on during the molt. I have had both birds examined under anesthesia and there is nothing to comment on concerning the use of this mounting method on these two birds.

"The old light colored bird, LittleChief, lost 2 decks, one 7 years ago. This and the problem with electrocution is my reason for changing to the backpack.

"I am completely satisfied with the method and can think of nothing negative to say other than I have experienced a couple of birds, and have heard of at least one more, that would not accept it initially (picking and getting beak caught). Your new crimping the metal sleeve eliminates the problems of removing stitches, which was the primary fault of the old methods."
Dr. Ken Riddle

Image Gallery

Side view
Side view Side view
Down on Sag...
Down on Sage Grouse, with TrackPack Down on Sage Grouse, with TrackPack
Andrew Elli...
Andrew Ellis Painting showing TrackPack from behind Andrew Ellis Painting showing TrackPack from behind
Going up (M...
Going up (Mark Williams photo) Going up (Mark Williams photo)
Female Cass...
Female Cassini with TrackPack Female Cassini with TrackPack
Older pereg...
Older peregrine with TrackPack Older peregrine with TrackPack
Passage pra...
Passage prairie from above, with TrackPack Passage prairie from above, with TrackPack
TrackPack m...
TrackPack mounted RT TrackPack mounted RT
Clear view ...
Clear view (Mark Williams photo) Clear view (Mark Williams photo)
Ready to go...
Ready to go (Mark Williams photo) Ready to go (Mark Williams photo)
Ralph Roger...
Ralph Rogers' gyrkin Ralph Rogers' gyrkin
Michael Gar...
Michael Garcia bird coming down with Bullet lid Michael Garcia bird coming down with Bullet lid
Both transm...
Both transmitters Both transmitters
Gyr/Merlin ...
Gyr/Merlin Hybrid with Micro TrackPack Gyr/Merlin Hybrid with Micro TrackPack
After the H...
After the Hunt with TrackPack (Mark Williams photo) After the Hunt with TrackPack (Mark Williams photo)
lunging cas...
lunging cassini from behind lunging cassini from behind
Open wide (...
Open wide (Mark Williams photo) Open wide (Mark Williams photo)
Goshawk wit...
Goshawk with TrackPack Goshawk with TrackPack
Young pereg...
Young peregrine with TrackPack Young peregrine with TrackPack
Coming in w...
Coming in with TrackPack Coming in with TrackPack
PowerMax on...
PowerMax on TrackPack (Mark Williams photo) PowerMax on TrackPack (Mark Williams photo)
Black Gyrki...
Black Gyrkin with TrackPack Black Gyrkin with TrackPack
Both transm...
Both transmitters Both transmitters
Silver gyrk...
Silver gyrkin with backpack and tail mount Silver gyrkin with backpack and tail mount
PowerMax on...
PowerMax on a tiercel Peales held by young Apprentice PowerMax on a tiercel Peales held by young Apprentice
Closing in ...
Closing in on a duck (Mark Williams photo) Closing in on a duck (Mark Williams photo)
Female Pere...
Female Peregrine with TrackPack Female Peregrine with TrackPack
Bullet lid ...
Bullet lid on RT+ Bullet lid on RT+
Mark Willia...
Mark Williams casting off Mulligan with tail and backpack transmitters Mark Williams casting off Mulligan with tail and backpack transmitters
Young pereg...
Young peregrine with TrackPack Young peregrine with TrackPack
Merlin with...
Merlin with Micro TrackPack Merlin with Micro TrackPack
Howard show...
Howard shows the new passage Prairie Howard shows the new passage Prairie
Three sizes...
Three sizes of TrackPack Three sizes of TrackPack
Patrick Mor...
Patrick Morel with RT Turbo 433 mounted up high Patrick Morel with RT Turbo 433 mounted up high
Side view
Side view Side view
TrackPack m...
TrackPack mounted falcon takes a crow TrackPack mounted falcon takes a crow

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Price with discount $35.00
Sales price $35.00
Sales price without tax $35.00