Leg Curl / Leg Extension Rack Attachment

Name: Leg Curl / Leg Extension Rack Attachment
Brand: Bells of Steel
Rating: 2.17 (4 reviews)

Bells of Steel’s Leg Curl/Leg Extension Rack Attachment mounts onto a power rack’s uprights to add seated leg extensions and standing single-leg hamstring curls without the floor space of a dedicated machine. It’s built for a machine-like feel — a padded, rotating leg pad on an adjustable seat, with UHMW lining at the rack contact points so it doesn’t scratch the upright — and loads from a plate peg rather than a weight stack. It ships in three fitment variants to match different rack tube/hole sizes: Manticore (3”x3”, 1” holes), Hydra (3”x3”, 5/8” holes), and a generic 2.3”x2.3” (5/8” holes) option. The rack it’s mounted to must be bolted down while using it, and Bells of Steel recommends running it on the inside of the rack for maximum stability.

Material	Steel construction with UHMW lining at rack contact points
Seat/pad	Adjustable seat position; leg pad rotates vertically or horizontally
Plate peg	10.8" loadable length, rubber stopper, holds up to five 45 lb plates per side
User capacity	250 lb
Rack compatibility	Manticore (3"x3", 1" holes), Hydra (3"x3", 5/8" holes), or 2.3"x2.3" (5/8" holes)
Weight plate capacity	250 lb

What is a Rack Attachment?

What rack attachments are

Rack attachments bolt or pin onto a power rack or squat stand to expand what it can do — J-cups and safety arms/straps (the essentials), plus dip bars, a landmine, a lat pulldown, weight-plate storage, roller J-cups, and more. They turn a rack into a whole gym.

Compatibility comes first

An attachment must match your rack’s upright size (2x2, 2x3, or 3x3) and hole pattern/hardware (e.g. 5/8-in vs 1-in holes, Westside spacing). Attachments are usually series-specific — a Monster Lite J-cup won’t fit an Echo upright — so confirm the fit before buying.

How it compares

	Leg Curl / Leg Extension Rack Attachment	REP® Belt Squat	Rotator Voltra Add-on	ISO Arms
GymRadar rating	2.17/5	2.27/5	2.53/5	2.72/5
Price		$309.99	$159.00	$559.99
Material	Steel construction with UHMW lining at rack contact points
Seat/pad	Adjustable seat position; leg pad rotates vertically or horizontally
Plate peg	10.8" loadable length, rubber stopper, holds up to five 45 lb plates per side
User capacity	250 lb
Rack compatibility	Manticore (3"x3", 1" holes), Hydra (3"x3", 5/8" holes), or 2.3"x2.3" (5/8" holes)
Weight plate capacity	250 lb

2.2/5 · 4 GymRadar reviews

Reviews by source

Expert	2.17/5	4 reviews
Retailer	4.6/5	44 reviews

Bells of Steel’s leg curl/extension attachment is well-made but poorly conceived: reviewers consistently praise the steel gauge and finish while faulting the actual exercise mechanics, and the two signals converge unusually cleanly here. One in-depth YouTube reviewer explains the flaw precisely — as a rotating-lever attachment there’s almost no resistance for the first half of the range of motion, ramping to maximum only at full extension, which he calls disqualifying for leg extensions specifically (a band on the plate peg helps, but doesn’t fix it). GymRadar’s five owner reviews average just 2.07/5 and add a second, independent complaint: a loose fit on the rack upright that shakes under load. Functionality is the clear weak dimension; build materials are the standout, undercut by inconsistent fit-and-finish QC on arrival.

+Build quality: thick steel gauge and UHMW-lined rack contact points that don't mark up the upright (Bells of Steel product page; YouTube — djoDadOf2)
+Build quality: fit and finish described as commercial-gym quality on arrival, smooth-moving hardware (YouTube — djoDadOf2)
+Versatility: works with resistance bands, and the eyelet allows rigging to a low-row cable for added tension through the sticking point, though a plain band on the peg is the easier fix (YouTube — The Home Gym Life Project; YouTube — Halveye Helptu)
+Functionality: leg curls fare noticeably better than leg extensions — several reviewers found the resistance curve acceptable for curls even though extensions are the weak exercise (YouTube — djoDadOf2; YouTube — The Home Gym Life Project)

−Functionality: almost no resistance through roughly the first half of the leg-extension range of motion, ramping to maximum only near full extension — a rotating-lever design flaw, not a fluke (YouTube — djoDadOf2; GymRadar, Cameron DeMicoli, Narrow Pavlo)
−Build quality: multiple owners report a loose fit on the rack upright that rocks or shakes under load, even after shimming (GymRadar — ChanceB-LionsDen, Cameron DeMicoli; YouTube — Halveye Helptu)
−Value: reviewers call it overpriced for what it delivers, and several resold it to recoup money rather than keep using it (GymRadar — ChanceB-LionsDen, Narrow Pavlo)
−Build quality: quality-control complaints on arrival — chipped/worn powder coat, scratches, a misaligned loading sleeve, and pop pins that stick or mis-thread (GymRadar — ChanceB-LionsDen; manufacturer on-site reviews)
−Functionality: heavy and awkward to attach/detach from the rack, which reviewers say discourages swapping it in and out for leg day (GymRadar — Narrow Pavlo, ChanceB-LionsDen)