Captain America Weight Plates

Name: Captain America Weight Plates
Brand: Onnit
Rating: 3.33 (4 reviews)

The Captain America Shield Barbell Plate was Onnit’s officially licensed Marvel collaboration, part of a short-lived “Hero Elite Series” of superhero-themed equipment launched in 2016 (alongside an Iron Man kettlebell and Spider-Man battle ropes). Each plate is a urethane-coated, steel-core bumper plate styled after Captain America’s shield, designed to be dropped like a standard bumper with minimal bounce. It shipped only in 25 lb, 35 lb, and 45 lb pairs – there was never a fractional, 10 lb, 15 lb, or 55 lb version – and its diameter runs a few millimeters larger than a standard Olympic bumper plate, something reviewers and owners both note when mixing it into a set with other plates. Onnit discontinued the entire Marvel line years ago; it is no longer sold new by Onnit or any authorized retailer, and today it survives only as a sought-after collector’s item on the secondary market.

Buying guide

Best Weight Plates for Your Home Gym — July 2026 Bumper Plates or Iron Plates? How to Pick Your First Set — July 2026 Do You Need Calibrated or Competition Plates? — July 2026 How Much Do Weight Plates Cost Per Pound? — July 2026 What Weight Set Should a Beginner Buy? — July 2026 Will Dropping Weights Damage Your Floor? — July 2026

Design	Officially licensed Captain America shield graphic, raised weight lettering, Onnit + Hero Elite Series branding
Diameter	Standard Olympic bumper diameter, but runs a few millimeters larger than typical urethane bumper plates per reviewer comparisons
Material	Urethane exterior over a solid steel core
Center hole	Standard 2" Olympic bore; reviewers note it fits looser than most premium urethane plates
Availability	Discontinued -- no longer sold new by Onnit or any authorized retailer
Manufacturer	Onnit (Hero Elite Series, Marvel-licensed)
Available weights	25 lb, 35 lb, 45 lb (sold in pairs only)

What is a Weight Plate?

What weight plates are

Weight plates load your barbell — but “plate” covers two very different tools. Bumper plates are rubber discs around a steel hub, all the same ~450mm diameter, built to be dropped from overhead without damaging your floor or bar; they’re the default for Olympic lifting and CrossFit. Iron/steel plates are denser and thinner per pound, cheaper, and quieter to load, but most aren’t made to be dropped — better for slow, controlled powerlifting-style work.

What actually matters

Bumper vs. iron. Buy bumpers if the bar might hit the floor; iron (or rubber-coated iron) for controlled lifts and compact loading.
Weight tolerance. How far a plate strays from its stated weight (±1% is tight, ±3% loose). It barely matters for general training but adds up if you chase a specific total — which is why serious lifters add small change / fractional plates.
Collar fit & bounce. The center hole should fit your bar’s sleeve snugly; rubber durometer (around 88 Shore A) controls how “dead” a dropped plate lands.
Coating & set composition. Virgin rubber holds up and smells less than recycled crumb rubber; plan a starting set (usually a pair each of 45/25/10/5 lb plus change plates) around the lifts you actually do.

Who it’s for

Every barbell gym needs plates. Most home lifters should start with a bumper set, then add iron, change, or specialty plates as a second purchase once they know what their training is missing.

How it compares

	Captain America Weight Plates	Iron Grip Urethane Olympic Barbell Plates UPT12	Rogue Bumper Plates by Hi-Temp	Fractional Iron Plates - 0.5 LB
GymRadar rating	3.33/5	3.27/5	3.4/5	3.22/5
Price		$15.40	$55.00	$31.99
Design	Officially licensed Captain America shield graphic, raised weight lettering, Onnit + Hero Elite Series branding			Hexagonal profile
Diameter	Standard Olympic bumper diameter, but runs a few millimeters larger than typical urethane bumper plates per reviewer comparisons	45 lb 17.5in / 35 lb 14.375in / 25 lb 12.5in / 10 lb 9.5in / 5 lb 7.75in / 2.5 lb 6in	445mm (below the 450mm Olympic standard)
Material	Urethane exterior over a solid steel core	cast iron core, urethane coating	Crumb rubber (recycled vulcanized rubber) with 2" stainless steel insert	Cast iron
Center hole	Standard 2" Olympic bore; reviewers note it fits looser than most premium urethane plates			52mm (fits standard 2" Olympic barbell sleeve)
Availability	Discontinued -- no longer sold new by Onnit or any authorized retailer
Manufacturer	Onnit (Hero Elite Series, Marvel-licensed)
Available weights	25 lb, 35 lb, 45 lb (sold in pairs only)

3.3/5 · 4 GymRadar reviews

Reviews by source

Expert	3.33/5	4 reviews
Youtube	4.3/5	3 reviews
Reddit	4.5/5	6 reviews

The Onnit Captain America Shield Barbell Plate turns a standard bumper plate into a licensed Marvel collectible, and reviewers who actually trained with it come away impressed rather than just charmed by the novelty. Its standout dimension is functionality: the urethane construction keeps bounce to a minimum and, at 45 lb, is noticeably thinner than most bumper plates – Basement Brandon calls it thinner than offerings from Rogue’s Echo bumpers or Titan, which matters if you’re trying to load a lot of weight onto one bar. Its weakest dimension is versatility: it only ever shipped in 25/35/45 lb pairs (no fractional or 10/15/55 lb options), and its outer diameter runs a few millimeters larger than a standard bumper, which owners on r/homegym and in video reviews both flag as awkward when mixing it into a set with other plates. Onnit discontinued the whole Marvel “Hero Elite Series” line years ago, so this is a collector’s item rather than a buyable product today – reviewers consistently note the surface is more slippery than a typical urethane plate and the center bore runs looser than expected, but nobody reports a durability failure.

+Functionality: urethane construction with a steel core keeps bounce minimal and holds up to repeated dropping (Buffville Gym, Basement Brandon)
+Functionality: at 45 lb, noticeably thinner than comparable urethane bumper plates from Rogue, Titan, and American Barbell, letting more weight fit on a bar (Basement Brandon)
+Build quality: weighed out perfectly on a scale to its stated 45 lb, with distinctive raised lettering and Onnit/Hero Elite Series branding (Buffville Gym, Garage Gym Reviews)
+Value: licensed Marvel design draws attention and enthusiasm wherever it's used -- repeatedly called "badass" and a build centerpiece across r/homegym and both YouTube reviews
+Durability: no failure or breakdown reports found across community threads or video reviews, even from owners using it as a daily-driver plate

−Versatility: only ever sold in 25 lb, 35 lb, and 45 lb pairs -- no fractional plates or larger/smaller sizes to round out a full set (Garage Gym Reviews, Basement Brandon)
−Versatility: outer diameter runs a few millimeters larger than a standard bumper plate, awkward when mixed with a normal plate set or loaded for deadlifts/squats (Basement Brandon, r/homegym)
−Build quality: surface is noticeably slippery -- "almost like it has a little bit of grease on it" -- with no lip to dig fingers into (Basement Brandon)
−Build quality: center bore is looser than typical, and gets looser with repeated reps/sets unless a collar is used (Basement Brandon; disputed by Buffville Gym, who considers it a non-issue)
−Value: Onnit discontinued the line years ago, so it's no longer purchasable new at any price -- only resale/collector listings exist today (r/homegym, confirmed via manufacturer page and former Rogue Fitness listing both now gone)