ONYX Forearm Trainer

Build forearms that match your arms.

Adjustable grip training in 5 minutes a day. Train at your desk, on the couch or at the gym.

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Build forearms that match your arms.
Stronger gripMore defined forearms5 minutes a dayTrain anywhereFree US shipping90-day guaranteeStronger gripMore defined forearms5 minutes a dayTrain anywhereFree US shipping90-day guarantee

Why forearms

The one muscle everyone sees.

Your shirt covers your chest, abs and biceps. Your forearms are out every time you roll up your sleeves, shake a hand or grab the wheel.

70%1

In one study, how strong a man looked explained about 70% of how attractive women rated his body.

#12

In a thread of 400+ comments from women sharing their turn-ons, forearms came up more than anything else.

20 lb3

Men ages 20 to 24 tested in 2016 had a right-hand grip about 20 lb weaker than men that age in 1985.

  1. Sell, Lukaszewski & Townsley, Proceedings of the Royal Society B, 2017.
  2. Cup of Jo reader thread, summarized by The Art of Manliness, 2024.
  3. Fain & Weatherford, Journal of Hand Therapy, 2016, compared with 1985 norms.
Big arms. Skinny forearms? 5 minutes a day

The problem

Big arms. Skinny forearms?

You train chest, back and biceps. Your forearms get whatever time is left at the end of the workout, if they get any at all. So they never catch up.

That's a problem, because in a T-shirt or rolled-up sleeves, your forearms are the part of your arms people actually see.

ONYX gives them their own five minutes a day. Set the resistance, squeeze, and let the counter keep score. On the couch, at your desk or between sets. No extra gym time.

Get yours

How it works

Five minutes. That's it.

No gym, no plates, no new routine. Just a few minutes of hard squeezes while you do something else.

  1. 01

    Set your resistance

    Turn the dial to choose how hard it squeezes back. Start light and go heavier as you get stronger.

  2. 02

    Squeeze for 5 minutes

    Slow, full squeezes on the couch, at your desk or between sets. Grab the 2-pack and train both hands at once.

  3. 03

    Beat your number

    The built-in counter tracks every rep. Beat yesterday's count, then turn the dial up a notch.

The difference

Why guys choose ONYX

Classic grippers have one fixed spring. Once it gets easy, you're done. ONYX keeps up as you get stronger.

ONYX Classic grippers
Adjustable resistance
Built-in rep counter
One tool from beginner to heavy
Free 30-day forearm plan
Fits in your bag

What to expect

Your progress timeline

Everyone's different, and results depend on how often you train. Here's what steady daily sets can look like.

  1. Week 1

    Feel it working

    You'll feel a deep forearm pump from your very first sessions.

  2. Week 4

    Grip gets stronger

    Heavier settings start to feel easier, and you'll beat your old rep counts.

  3. Week 6+

    See the change

    Keep it up and your forearms start to look fuller and more defined.

Try it for 90 days.

Train with ONYX for 90 days. If you're not happy with it, email us and we'll refund your order. No hoops. No hassle.

  • Free US shipping
  • 90-day money-back guarantee
  • Free 30-day forearm plan
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FAQ

Questions? We've got answers.

Is it good for beginners?

Yes. Start on the lightest setting and add resistance as your grip gets stronger. It works for first-timers and for guys who already lift.

Will it work if my forearms are just genetic?

Your wrist bones won't change, and nobody's can. The muscle on top of them can. Forearms are slow to grow for most guys, so the key is training them often. That's what five minutes a day is for.

When will I start noticing results?

Most guys feel the pump right away. Strength and size take steady work, so give it a few weeks of daily sets. Results are different for everyone.

Can I use it every day?

Yes, once you build up to it. Start on a light setting for the first week, and take a day off if your hands or forearms feel sore. If anything hurts, stop.

Do I still need other forearm exercises?

No. ONYX works on its own, and it fits right into your gym routine if you already have one.

How does the rep counter work?

It counts each full squeeze for you. Check your number after each set and try to beat it next time.

Should I get one or two?

Two lets you train both hands at the same time, so you're done in half the time. The 2-pack is also our best price per trainer.

What's your shipping and return policy?

Shipping is free on every US order, and you'll get tracking by email. You're also covered by our 90-day money-back guarantee. Just email support@onyxshreds.com.