Make Your SelectTechs^®
Better Than OEM^™

In a word: No. When the original manufacturer’s molded plastic discs lead to a recall of nearly 4 million pairs of dumbbells spanning more than 20 years, it’s a clear sign that plastic is the wrong material for the job. 3D printed plastics might be excellent for some applications, but they are fundamentally unsuitable for the discs and locking pins in this design. The manufacturer couldn't make plastic work with a multi-million dollar budget; do you really believe an eBay or Etsy seller with a 3D printer is going to have better luck making a part that’s safe enough to hold 50-90 lbs over your head?

Bench Test: 3D-printed plastic disc snapping under light load conditions.

Since 2019, I have bench-tested dozens of discs and locking pins. In my controlled load tests, every OEM and 3D-printed part failed at forces significantly lower than my metal alternatives. While no component is indestructible, my aluminum and steel parts provide a massive margin of safety that plastic simply can't match.

It is honestly baffling to see these plastic replacements selling online for $10 to $20+ each. For roughly the same price, or less, you can upgrade to solid metal. When you're holding 50-90 lbs in each hand, over your face, plastic simply isn't up to the task. There’s a reason commercial gym equipment is built mostly from metal.

No. SelectTech and Results Series dumbbells—whether stock or upgraded—are not designed to be dropped or used to support bodyweight.

Drops and bodyweight exercises generate forces that are far higher than those seen during normal use, such as presses, rows, curls, or flys. While Average Joe Disc Fix Kits and Locking Pin Kits improve durability during ordinary training, they are not indestructible.

For this reason, damage caused by dropping the dumbbells or using them as push-up handles is not covered under warranty. Always set the dumbbells down on the floor or in their bases between sets.

It's also worth noting that even if upgraded components survive an impact, other parts—such as dials, crossbars, shafts, bases, or weight plate tabs—may not.

The Short Answer: Maybe, but it’s a gamble.

These dumbbells were mass-produced for years with “loose” manufacturing tolerances, meaning no two sets are exactly alike. In my experience, even genuine OEM parts can vary significantly from one pair to the next. Most sellers online are simply “parting out” old, discontinued units; they remove a part from a 552 or 1090 and list it as compatible without realizing it may have come from a slightly different version. They aren't being deceptive—they just haven't spent years obsessing over the nuances of these dumbbells like I have.

Just because a part is advertised for your model doesn’t guarantee a drop-in fit. You’re essentially “buying to try,” and if it doesn’t fit, you're at the mercy of a stranger's return policy.

I designed my upgrade kits to account for the widest possible variance in manufacturing. While 95% of installs are perfectly plug-and-play, I’ve built the video guides and support systems to walk you through the “fine-tuning” process if your set happens to be one of the 5% of outliers.

Short answer:
Yes. Average Joe Disc Fix Kits work with the vast majority of OEM and knockoff 552 and 1090 dumbbells right out of the box.

Long answer:
As mentioned in the previous answer, my kits are designed to fit about 95% of sets with no modifications. If you happen to have a “unique” set that falls into the other 5%, you have two simple options:

1. Fine tune the fit: Most fit issues are solved with straightforward DIY adjustments. I have specific guides on shimming or sanding/filing the discs or weight plates to improve clearance. Even a fraction of a millimeter can make the difference, and I have videos to walk you through it.

2. Plan B: If the parts won't fit and you don't want to tweak them, you are covered by my 30-day guarantee. You can return them for a refund minus the original shipping cost, payment processing fees, and sales tax . While return shipping is your responsibility, I do not charge a restocking fee.

See Average Joe 30-Day Guarantee & 10-Year Limited Warranty for full details. If you're ready to see if they'll work for you, place an order and I'll get the ball rolling.

Yes. Customers are already successfully installing my grips, locking pins, dials, and end caps on their brand-new Results Series sets today, straight out-of-the-box.

A quick look under the hood of the “new” model shows most of the parts remain virtually identical to the older models, so compatibility is the same as with SelectTechs.

Meet the new boss, same as the old boss

Whether you have classic SelectTechs or the latest Results Series, you're using fundamentally the same dumbbells. My upgrades are built for both. They fix the remaining factory weak points and make your dumbbells more solid, dependable and easy to use, just like they should have been from day one.

Whether the Results Series fully resolves every cause of plate detachment remains to be seen. My other upgrades address several contributing factors the manufacturer has never publicly acknowledged.

Yes, most knockoff dumbbells are compatible. Generally, if your dumbbells are a direct visual clone of the SelectTech 552 or 1090 design, the AJI discs and locking pins will fit. Because these clones are built using the same “loose” manufacturing tolerances as the originals, the same rules apply: while most are a straightforward swap, some may require fine-tuning due to variances in the knockoff's components.

The short answer is: You can’t go wrong. I chose these materials because they are what I wanted for my own dumbbells. I originally moved to Aluminum because it was a massive, affordable upgrade over factory plastic when I was fixing my own sets. A few years later, I finally added Stainless Steel—the material I always wanted from day one, but was out of my budget at the time. I offer both so you can decide how far you want to take your upgrade.

The Aluminum disc kits are my “workhorse” solution. They are durable, high-strength, and designed to replace the plastic internals with metal that won't give up on you. If you just want a set of dumbbells that are reliable and built to last without spending a fortune, this is the way to go.

All 5 of my upgrades a.k.a “The Works”

The Stainless Steel disc kits are my “money-is-no-object” solution. These are for the person who wants to go all the way. It’s about the bump in weight and raw-steel look, and that “built like a tank” feel every time you pick them up. It gives your dumbbells the weight and presence of high-end commercial gym equipment.

Both materials are naturally corrosion-resistant and will likely outlast the dumbbells themselves. You aren’t choosing between better and best; you’re just choosing how you want your dumbbells to feel for the next twenty years.

Yes. Cast aluminum discs can be purchased and installed individually.

Factory seconds are kits that are functionally identical to my standard kits but have cosmetic imperfections — nicks, scratches, spots/stains, or irregular casting/knurling — that fall outside my standard quality control. What constitutes a factory second is determined solely by my quality control standards, and that determination is final.

Minor surface variations that are only noticeable under close inspection — such as slight casting differences or minor tooling marks — do not constitute factory seconds and are characteristic of hand-finished metal components.

The Trade-off: You get a 25% discount in exchange for these blemishes. These parts are structurally sound and provide the same performance as my standard kits. The imperfections are purely surface-level and do not compromise the integrity of the hardware.

The Terms & Conditions:

• All factory seconds sales are final. Please consider the cosmetic blemishes before ordering.
• Returns: Accepted within 30 days only for verified fitment/compatibility issues.
• Non-Refundable: Shipping, taxes, and payment processing fees are non-refundable for any reason.

It’s really just a matter of following the steps. If you're used to working with your hands, you can probably finish a disc upgrade in 10 to 30 minutes. If you're new to DIY, just follow along with my videos and plan for about 30 to 60 minutes for your first one. Most people find that once they get the first dumbbell done and see how the parts fit together, the second one is a piece of cake.

Not in the traditional sense. Kit pricing starts at $10–$12.50 per disc depending on your model, and for that you’re getting solid aluminum — a material that has outperformed every OEM and 3D-printed plastic disc I’ve ever bench tested — for roughly the same price as the plastic alternatives, or less.

That said, there are two exceptions worth knowing about:

Factory Seconds — Occasionally, a batch of kits will come in with cosmetic imperfections that fall outside my standard quality control. The parts are structurally identical and perform the same; they just might have nick, dings, or other cosmetic blemishes. When they’re available, factory seconds are offered at a 25% discount. Availability is unpredictable — I can’t guarantee they’ll be in stock when you order, and I can’t always predict when the next shipment will arrive, if it will contain any seconds, or how tariffs may affect pricing down the road. If you’d like to be notified when factory seconds are available, consider signing up for my email newsletter for updates.

Volume Orders — If your total before shipping exceeds $500, I apply a 10% discount automatically.

Outside of those two situations, the price is the price — and I’m confident it’s the right one for what you’re getting.

New Customers: Click on the “Get Some Upgrades” or “Get Yours” buttons to open the AJI order form. Once you submit that, I’ll review it and email you an invoice through Paypal, by default. If you prefer Venmo, Zelle, or Revolut, just mention that in the “Additional Information” box.

Existing Customers: You get the “Fast Track.” Skip the form and just email me directly with what you need. As long as your info is in my database and hasn't changed, I'll send the invoice straight over.

Yes. All Average Joe Kits currently in production are backed by a 30-Day Guarantee & 10-Year Limited Warranty.

Legacy kits: 1st and 2nd Generation Disc Fix Kits are no longer under warranty. I continue to provide unofficial support for these older kits as long as I have spare parts available; part and shipping charges may apply. Spare inventory is sufficient for the foreseeable future.

Policy updates: I reserve the right to update the guarantee and warranty at any time. Changes apply only to purchases made on or after the publication date of the revised policy.

Yes. I ship worldwide via USPS, UPS or FedEx provided service is available to your location. Every shipment is trackable. I’ve sent kits to customers on 6 continents. When you submit your order form, I’ll calculate the best current rate for your specific address and include it in the invoice.

U.S. Orders: Most kits ship via USPS, UPS and Fedex. Fees generally range from 10-25+ depending on the size and weight of the order. If you have a specific courier you prefer in your neighborhood, or one you know to avoid, let me know in your order request and I will do my best to accommodate you.

International Orders: FedEx is currently the most reliable and affordable option for most overseas shipments, usually ranging from $20–$50+. If you have a specific courier you prefer in your country, let me know in your order request and I will do my best to accommodate you. Contact me for a precise estimate before ordering.

U.S. Customers: State and local sales/use tax will be added to your invoice when and where applicable by law.

International Customers: Your AJI invoice does not include VAT, import duties or brokerage/handling fees. You are responsible for paying these fees to the courier and/or your country's customs agency when the package arrives. They will contact you directly for payment. Please keep this in mind so you aren't taken by surprise.

If the tracking shows “Delivered,” the courier has fulfilled their contract. Average Joe Innovations does not provide free replacements for stolen packages or shipments lost by the courier. You will need to file a claim with the courier directly. Risk of loss and title for all products pass to the customer upon my delivery to the carrier; by paying your invoice, you acknowledge and accept all risk for packages lost in transit or stolen after delivery.

Most standard shipments include up to $100 of insurance coverage by default. If your order value is higher and you’d like to be fully insured, please request it on your order form and I will provide a quote for the additional coverage.

My Recommendation: If you’re concerned about porch pirates or neighborhood theft, spend the additional $4+ for a Signature Requirement. You can request this on your order form. It’s the cheapest protection you can buy to ensure the gear actually makes it into your hands.

No. Falsifying export information is a federal offense under 13 U.S. Code § 305, carrying heavy fines and potential jail time. I value my business (and my freedom) too much to take that risk. I respectfully ask that you do not request this. Thank you for understanding.

Since July 2020. Average Joe Innovations didn’t start as a business plan; it started as a personal mission.

For years, I dealt with the same failures many of you are experiencing. I tried everything, from buying used parts online to experimenting with cheap DIY fixes, but nothing held up for long. I grew up in a family where we didn’t throw things away just because they were broken...we fixed them. We believed in getting as much life as possible out of our investments, so in 2019, I finally got fed up and decided to stop patching the problem and actually solve it.

I designed metal discs to replace the plastic discs that kept failing. After sharing the process on YouTube in 2019, it became clear I wasn’t the only one looking for a better solution.

Since then, what started as a personal project has grown into a full-time commitment serving many thousands of customers worldwide. I still work directly with the same manufacturers in the U.S. and overseas that I’ve used from the very beginning, ensuring that every part continues to meet the standard I wanted for my own gear. I’m still just an Average Joe who believes that if you make an investment in your health, that equipment should last.

I handle every aspect of this business personally, from design to shipping and customer support. This means you get answers directly from the person who engineered the parts, not a chatbot or a call center script. I typically respond within 24-48 hours. If it takes a little longer, it's because I'm in the shop getting orders out the door.

No. AJI is not affiliated with any OEM manufacturers. Bowflex® and SelectTech® are registered trademarks, and Results Series™ is a trademark, of Johnson Health Tech Retail, Inc. These companies have had no involvement in the development, marketing, or sale of AJI products, which are not endorsed by them.