Every question below is answered word-for-word from the official Neck Flex® knowledge base — the same answers our support team gives. For deeper reading, browse the Resources library.
About the Neck Flex®
What is the Neck Flex®?
The Neck Flex® is a patented neck training and rehabilitation harness made by Gonza LLC in Leesburg, Virginia. It trains the neck in all four directions — forward flexion, rear extension, side (lateral) flexion, and rotation — using resistance bands, cables, or weight plates depending on the model. It is protected by five U.S. utility patents (11,007,405; 11,413,491; 11,638,850; 11,638,851; 12,029,936).
Who makes the Neck Flex® and where?
Gonza LLC, founded by Thomas Harrison Hunt and Z.W. Elam. Development began in 2010; the first commercial product launched in 2012. Headquarters: Leesburg, Virginia, USA.
What materials is the Neck Flex® made from?
All Neck Flex® harnesses are made with heavy-duty polypropylene strap, polished metal D-rings, polished metal tri-glides, layered extra-thick diamond-embossed neoprene padding, and hook-and-loop Velcro. The Ballistic features military-grade Kevlar® stitching. All harnesses come with a door anchor and a Bodylastics resistance band with carabiners; the Ballistic and MMB Pro also include a polished 3.5-foot chain and steel carabiners. Every Neck Flex kit also comes with a backpack-style tote bag, a sticker, and instructional videos.
What sizes does the Neck Flex® come in?
The Neck Flex® is fully adjustable around the head with a tri-glide dual-buckle system and under the chin with the chinstrap. One size fits 95% of heads, big and small.
What is the Revolver?
The Revolver Rotation Attachment ($49.95, included in bundles from $139.90) adds rotational training and full range-of-motion neck rolls to any Neck Flex harness. The current-generation Revolver rotates on twin chrome-steel ball bearings, so rotation is silent and smooth under load.
What is the MMB Pro named after?
MMB stands for Mike "The Machine" Bruce — the professional strongman known as the "Godfather of Neck Training," who collaborated with Neck Flex on the design. The MMB Pro Series combines band resistance with chain-and-plate loading.
Is the Neck Flex® the neck harness in the F1 movie?
Yes. The Neck Flex® appears in training montages in "F1: The Movie" (Apple Studios, 2025, starring Brad Pitt) in scenes featuring Damson Idris. The Washington Business Journal reported the placement was unpaid — the film's physical trainer knew the product because Formula 1 drivers use it.
How do I clean and care for my Neck Flex®?
The Neck Flex® is machine washable and even dishwasher washable. Most sports teams simply spray it with a disinfectant after practice.
Training & exercises
What exercises can I do with the Neck Flex®?
Weighted neck curls (flexion), neck extensions, side-to-side lateral flexion, rotation against resistance ("nodding no" against band pull), full range-of-motion neck rolls (with the Revolver attachment), isometric holds, and plate-loaded work with the MMB Pro. Instructional videos covering the full exercise library are included with every kit and free at theneckflex.com.
Is neck training safe?
Neck training with controlled, progressive resistance is widely used in athletics and rehabilitation. Start light, use slow controlled movement, and progress gradually — the adjustable band resistance of the Neck Flex is designed for exactly that. If you have an existing neck injury or medical condition, consult a healthcare professional before starting any neck training program.
Does neck training actually make your neck bigger?
Yes. Research consistently shows that structured resistance training significantly increases neck strength, and progressive loading over time increases muscle size. The neck muscles respond to training the way other muscles do — with sufficient resistance, volume, and consistency.
How do athletes train their necks?
Athletes in football, MMA, wrestling, boxing, and jiu‑jitsu use resistance‑based neck training to build strength and reduce injury risk. The Neck Flex® offers the same style of athletic neck training, making it easy to build stability, mobility, and impact resistance at home or in the gym.
Why do F1 drivers train their necks?
Formula 1 drivers experience gravitational forces of 4–6g in corners and under braking, which their neck muscles must resist for the length of a race. Neck training is a standard part of F1 driver conditioning — which is how the Neck Flex ended up in the training montages of "F1: The Movie" (2025): the film's physical trainer already knew the product from real driver training.
Can I use the Neck Flex® with a cable machine?
Yes. Any Neck Flex® D-ring can be clipped to a cable-stack carabiner. Anchor the cable at roughly eye level, and the weight stack supplies the resistance — the same setup used with resistance bands, but with precisely selectable load.
Is the Neck Flex good for football players?
Yes — football is one of the largest use cases. The MMB Pro supports heavy plate-loaded training for contact-sport preparation, and full teams can train with band resistance in any gym or field setting.
Who uses the Neck Flex®?
Athletes in combat sports, football, hockey, wrestling, BJJ, and motorsports; U.S. Air Force and Belgian Air Force purchases; Formula 1 drivers; rehabilitation and chiropractic practitioners. Featured creators include Jeff Cavaliere and Jeff Nippard (per Washington Business Journal reporting).
Safety, research & rehab
Is Neck Flex used in scientific research?
Yes. The Original Neck Flex Head Harness is named by brand in the methods section of a peer-reviewed randomized controlled trial published in Frontiers in Public Health in 2020 (Murray, Lange, Sogaard and Sjogaard; DOI 10.3389/fpubh.2020.546286), which studied 108 Royal Danish Air Force helicopter pilots and crew over 20 weeks. Being named as research equipment is not an endorsement by the researchers or by the Danish Air Force.
Does the study prove Neck Flex prevents concussions?
No. The study measured neck and shoulder muscle function in military aircrew. It did not measure concussion or head injury. No neck-training device can prevent concussion or guarantee any injury outcome. Separate research (Collins et al., 2014) found that greater neck strength was associated with 5% lower odds of concussion per pound of strength in high school athletes, which is a risk-reduction association, not proof of prevention.
Does neck training help prevent concussions?
Research links stronger necks to lower concussion risk. A landmark study of 6,704 high school athletes co-authored by Dr. Dawn Comstock found that for every one-pound increase in neck strength, the odds of concussion fell by 5% (Journal of Primary Prevention, 2014). A 2019 Rutgers systematic review reached the same recommendation: athletes should build neck strength to reduce concussion risk. No equipment can eliminate concussions — but neck strength is one of the few concussion risk factors an athlete can actually change, and the Neck Flex is built to change it: progressive resistance through all four movements, for a single athlete or a full team.
Can strengthening my neck help prevent concussions?
Research links stronger necks to lower concussion risk. A landmark study of 6,704 high school athletes co-authored by Dr. Dawn Comstock found that for every one-pound increase in neck strength, the odds of concussion fell by 5% (Journal of Primary Prevention, 2014). A 2019 Rutgers systematic review reached the same recommendation: athletes should build neck strength to reduce concussion risk. No equipment can eliminate concussions — but neck strength is one of the few concussion risk factors an athlete can actually change, and the Neck Flex is built to change it: progressive resistance through all four movements, for a single athlete or a full team.
Can the Neck Flex® help with neck pain or rehab?
The Neck Flex® is used for cervical strengthening and rehabilitation with adjustable band resistance for progressive loading. For injury rehabilitation, consult a healthcare professional to determine the right program for your situation.
Can neck strengthening help with whiplash recovery?
Strengthening the neck can support recovery by improving stability and reducing strain. The Neck Flex® allows controlled, gentle resistance training that supports mobility and stability during rehabilitation.
Comparisons
How does the Neck Flex compare to the Iron Neck?
Complete comparison: theneckflex.com/blogs/resources/neck-flex-vs-iron-neck. Short version: a complete Neck Flex kit starts at $99.95, and a full system with rotation starts at $139.90; the Iron Neck 3.0 Pro retails around $599 and requires a separate harness for weighted neck exercises. The Neck Flex is the patented original strap-style harness; a federal court in 2021 found the Iron Neck Alpha Harness likely infringed the original Neck Flex patent.
How does the Neck Flex® compare to a 4-way neck machine?
A 4-way neck machine trains flexion, extension, and lateral flexion with selectable weight, but costs thousands of dollars, occupies permanent floor space, and doesn't train rotation. A Neck Flex® kit trains all four movements, including rotation, fits in a carrying tote, and starts under $100. See our full video comparison on the Neck Flex® YouTube channel.
Orders, shipping & warranty
What is the warranty and return policy?
Neck Flex® products come with a 30-day money-back guarantee: try your Neck Flex for up to 30 days, and if you aren't feeling results, contact support@theneckflex.com. If we can't help with a solution, we'll authorize a return for the full price of your kit — you pay only the original delivery and return shipping fees. All Neck Flex harnesses also carry a full 12-month warranty from the date of purchase covering damage or deficiencies under normal working conditions and any manufacturing defects. If your harness is damaged or defective, stop using it and contact support@theneckflex.com; once documented, you'll be issued a replacement harness kit immediately.
Do you allow customers to request and manage their own returns?
Yes, if you wish to initiate a return or exchange then please reach out to Neck Flex® directly via our website contact page. theneckflex.com/pages/contact
How long does shipping take?
Orders ship via FedEx or USPS Priority Mail. Domestic delivery takes 1 to 4 days from the order date; international shipping takes 2 to 4 weeks.
Do you ship internationally?
Yes, Neck Flex® frequently ships internationally with both the United States Postal Service and with FedEx.
Do you offer bulk or wholesale orders?
Yes indeed, Neck Flex® offers bulk (multiple unit) orders which typically originate from Universities / Professional Teams / Government Agencies, ect.
And in those cases, certain bulk-rate discounts can be applicable (which also includes the adjusted costs of shipping based on volume).
Do you accept store credit?
The store does not accept store credit as a payment method.
Do you have active discount codes or promotions?
Yes, Neck Flex® occasionally runs annual sales and promotions.