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BlackBear Fitness

BELLS OF STEEL / RACK ATTACHMENTS & COMPONENTS

Choose the fit for your setup.

Shoulder Boulder / Chest Fly Attachment

The Bells of Steel Shoulder Boulder / Chest Fly Attachment adds plate-loaded shoulder and chest isolation exercises to a compatible rack.

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£269.99

VAT included. Free shipping.

  • Shoulder and chest work
  • Two upright sizes
  • Match rack fitting
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Parts, adapters and upgrades

For compatible existing equipment. Select a part instead of the main product option.

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Check the selected option and product details for quantities, compatibility and included items. Other equipment shown in photos is for illustration.

Shoulder Boulder / Chest Fly Attachment

Bells of Steel reviews

Shoulder Boulder exceeds expectations

I have been using the Shoulder Boulder for a few weeks, and I am very pleased with it. For the price, it exceeds my expectations. It functions very well for a number of exercises. I’m abl...Read full review
I have been using the Shoulder Boulder for a few weeks, and I am very pleased with it. For the price, it exceeds my expectations. It functions very well for a number of exercises. I’m able to do lateral raises, rear raises, front raises, flat chest flys and incline chest flys. I store it high and to the side on the rear upright of my Rogue rack where it takes up little room and doesn’t get in the way of other lifts. I bring it down to the front when I want to use it. Fit and finish is fine. The 360 degree arm adjustment makes it easy to dial in each lift. It was packaged very well, and it arrived in perfect condition. I use it frequently and highly recommend it.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

Incentivised review

Superior to Dumbbell Flys for Chest and Shoulders!

I purchased this attachment because I want to incorporate fly movements into my workouts but have issues with dumbbell flys putting more strain on my shoulders than my chest and shoulders...Read full review
I purchased this attachment because I want to incorporate fly movements into my workouts but have issues with dumbbell flys putting more strain on my shoulders than my chest and shoulders. This attachment provides the most resistance where it is needed, in the middle of the movement, and tapers off at the start of the movement when the shoulder is most unstable.

It works perfect with my wall mounted 3x3 rack, and I use it for flat and incline chest flys and shoulder lateral raises. I love the squeeze I can get at the top of the chest fly movement that dumbbells simply cannot provide.

If there is one area of improvement is the threading on the back knob was tilted off center, so when I tighten the knob only one edge of it pushes on the back of the rack. This quickly damaged the rubber washer on the knob. It's an odd size, M16x3.0 mm, so not easy to find a replacement.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

Great addition

I really love using the shoulder boulder to train my shoulder over dumbbells, it just feels better during and after. I’m glad I added this to my home gym.Read full review
I really love using the shoulder boulder to train my shoulder over dumbbells, it just feels better during and after. I’m glad I added this to my home gym.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

Incentivised review

BOS Shoulder Boulder

This was easy to put together, easy to install, and man does it do a number on the shoulders! Solid piece of equipment, and it is extremely smooth to use. I haven't used it for chest flye...Read full review
This was easy to put together, easy to install, and man does it do a number on the shoulders! Solid piece of equipment, and it is extremely smooth to use. I haven't used it for chest flyes yet, but so far I really like it. Also, I'm pretty sure I can use my ankle strap to attach the cable to it instead of using plates only.

2.3" x 2.3" (5/8" Holes)

Cant wait to use it

Its very high quality. I have a monster g12 from Force Usa, the original version. My machine has 2×2 " tubing, so im having extra shims 3d printed to take up the slack. I also added a...Read full review
Its very high quality. I have a monster g12 from Force Usa, the original version. My machine has 2×2 " tubing, so im having extra shims 3d printed to take up the slack. I also added a sleeve adapter to take the 5/8'" stud up to a 1" to fit into my smith machine. So , there is a little more I need to put in to it to make a perfect fit for my machine, but in the end I already know it will be worth it. Its really an amazing compact device. Untill my 3d prints are done , I have it mounted on my attachment wall . Looks great with all my innovative gear. Perfect addition.

2.3" x 2.3" (5/8" Holes)

Incentivised review

Fantastic!!!

Just bought this and it’s great! Big time space saver since my gym is just a bedroom. It’s going to be a bit of a learning curve to figure out the setup for all of the different exercise...Read full review
Just bought this and it’s great! Big time space saver since my gym is just a bedroom. It’s going to be a bit of a learning curve to figure out the setup for all of the different exercises but so far a 10/10.

Thanks for making it to fit the uprights on the All-In-One trainer. Keep it up with your future ideas!

2.3" x 2.3" (5/8" Holes)

Mr

I love the Shoulder Boulder Attachment more with my 2 Ancore Units. Its smooth and eliminates the dead weight zone when using the small change plates. I mount the Shoulder Boulder on my...Read full review
I love the Shoulder Boulder Attachment more with my 2 Ancore Units. Its smooth and eliminates the dead weight zone when using the small change plates. I mount the Shoulder Boulder on my rack above the Seal Row Pad for Reverse Flys as I try to strengthen my "rehab-ing" shoulders. I attach the Ancores to the front leg and the lower crossmember using quick sliding rack adapters. Now I really need to find the room to mount a single post rack to permanently attach the shoulder boulder to so I can use this every day. Unfortunately, I have to remove this from my rack for daily lifting exercises.

Best Chest/ Shoulder attachment

The Bells of Steel chest and shoulder attachment is the best on the market! I love the easy to use and versatility it offers for any rack not just BoS. Add that extra ummpf to your worko...Read full review
The Bells of Steel chest and shoulder attachment is the best on the market! I love the easy to use and versatility it offers for any rack not just BoS. Add that extra ummpf to your workout without compromising space.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

Incentivised review

Decent space saving attachment

Takes a bit of work to get everything adjusted properly and setup. Not as nice as a stand alone piece, but does the job. I find the workout is better if you hook to cable machine instead ...Read full review
Takes a bit of work to get everything adjusted properly and setup. Not as nice as a stand alone piece, but does the job. I find the workout is better if you hook to cable machine instead of using free weights. Free weights don’t keep muscles under tension for full range in my opinion .
Incentivised review

Very nice attachment! Blows up the shoulders!

Have really enjoyed this attachment! It works well for lateral raises, single arm front raises, rear delt raises as well as pec flys! Great addition to my home gym.Read full review
Have really enjoyed this attachment! It works well for lateral raises, single arm front raises, rear delt raises as well as pec flys! Great addition to my home gym.
Incentivised review

5 Stars

Assembly was easy and it fits tight onto my Manticore rack with no wiggle. I got a nice shoulder shoulder pump. Definitely felt different then when i use dumbbells.Read full review
Assembly was easy and it fits tight onto my Manticore rack with no wiggle. I got a nice shoulder shoulder pump. Definitely felt different then when i use dumbbells.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

5 Stars

Awesome attatchment real isolates the body part you aim to target.Read full review
Awesome attatchment real isolates the body part you aim to target.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

Best in Class???

I’ve only had my Shoulder Boulder for a week at the time of this review, so I’m still dialing things in. As far as I know, this is the only unit in its class that can do a lying pec fly...Read full review
I’ve only had my Shoulder Boulder for a week at the time of this review, so I’m still dialing things in. As far as I know, this is the only unit in its class that can do a lying pec fly. The others I’ve seen only allow for standing pec flys, which don’t seem to offer the same stretch. I added roller pads to my Shoulder Boulder (see my video below), which allow more force to be generated in most movements. It’s not the same feel as lying pec fly or standing lateral raise machines, but for the money and footprint, it’s a value add for any home gym.
Incentivised review

Shoulder Boulder

Works well overall, would be 5 star if the hand grips had some movement Read full review
Works well overall, would be 5 star if the hand grips had some movement

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

3 Stars

Works fine. Quality is not the best and the knob was damaged. Will use for a bit then sell or trash.Read full review
Works fine. Quality is not the best and the knob was damaged. Will use for a bit then sell or trash.

3" x 3" (5/8" & 1" Holes) - Hydra & Manticore

Rack attachments & components

Details that matter

The facts, fitting notes and package information for this product.

The Bells of Steel Shoulder Boulder / Chest Fly Attachment adds plate-loaded shoulder and chest isolation exercises to a compatible rack.

Choose the correct fit

  • 3" × 3": Hydra and Manticore version for the listed 5/8" and 1" hole systems.
  • 2.3" × 2.3": version for compatible 60mm uprights with 5/8" holes.

Check the actual tubing dimensions and holes on your rack before ordering. Position the attachment at a suitable height for the exercise.

Use guidance

Ensure the rack or cable tower is securely anchored. Tighten the spin lock before each use and secure weight plates with suitable collars. Weight plates, collars, bench, rack and other optional accessories are sold separately.

Bells of Steel Shoulder Boulder/Chest Fly Attachment – image 2

Before you order

What does my selection include?

The option name identifies the size, finish, fitting or pack being purchased. Product details below list supplied items and any separately sold accessories. Quantity applies to that selected option.

How do I check compatibility?

Match the exact dimensions, rack system, hole size and mounting requirements stated for the selected option. Contact BlackBear if you are unsure before ordering.

Is shipping included?

Yes. Free shipping is included. Check the selected option and package details before ordering.

Product reviews

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