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Magnesium

Klean Magnesium

90 vegetarian capsules (SKU KA202599-90), 120 mg magnesium as magnesium glycinate per capsule

$26.50US price, checked Oct 24, 2026

120 mg magnesium glycinate capsule that NSF's Certified for Sport database lists

Check price at Klean Athlete Full review →

Magnesium

Momentous Magnesium Bisglycinate

60 capsules (30 servings)

$16.99US price, checked Oct 23, 2026

200 mg magnesium bisglycinate in two capsules, with an NSF sport listing

Check price at Momentous Full review →

Criterion	Klean Magnesium	Momentous Magnesium Bisglycinate
US price	$26.50Checked Oct 24, 2026 · Price details in the review	$16.99Checked Oct 23, 2026 · Price details in the review
Three-year ownership estimate	$348.91 Planning total.	$637.12 Planning total.
Choose if	You want a 120 mg magnesium glycinate capsule that NSF's Certified for Sport database lists, with lot numbers you can check.	You want a labeled 200 mg of magnesium bisglycinate in capsules, with an NSF sport listing, for under $17 a bottle.
Main trade-off	Klean's directions allow up to 480 mg a day, above NIH's 350 mg upper limit for supplemental magnesium.	A bottle lasts only 30 days, and delivered bottles generally can't be returned.
Key specifications	Dose per serving: 120 mg magnesium as magnesium glycinate per capsule (29% of the Daily Value). Klean's directions are 1 capsule, 1 to 4 times daily Servings per container: 90 capsules at 1 capsule a serving, on Klean's label and in NSF's listings Price per serving: About $0.29 a capsule at the $26.50 retail price, or about $1.18 a day at 4 capsules Dose vs. upper limit: One capsule is 120 mg, under the 350 mg adult upper limit for magnesium from supplements and medications. Three capsules reach 360 mg, and the four Klean's directions allow reach 480 mg Other ingredients: Hydroxypropyl methylcellulose (vegetarian capsule) and ascorbyl palmitate. The label has no allergen statement Certification: NSF Certified for Sport lists two US entries for the 90-capsule product, with 11 and 13 certified lots Free-of statements: Klean's page shows gluten free, GMO free, vegan and vegetarian icons. NSF's entries list gluten free, GMO free and vegan claims Warning: Klean's label says to consult a health professional first if you're pregnant or lactating, have a health condition or take medication Where to buy: Klean's page lists a retail price but asks for a login to add to cart. Its shop address forwarded to a Klean Athlete storefront on Amazon on Oct 24, 2026	Dose per serving: 200 mg elemental magnesium as magnesium bisglycinate (48% DV) per 2 capsules Servings per container: 30 (60 capsules at 2 per serving) Price per serving: About $0.57 at the $16.99 one-time price. On a subscription, about $0.42 for the first delivery ($12.74) and about $0.51 after that ($15.29) Certification: NSF Certified for Sport. NSF lists "Magnesium Bisglycinate" by Momentous as an unflavored capsule, 2 capsules per serving, package size 60, lot # "All" Other ingredients: Hypromellose, silica, magnesium stearate, microcrystalline cellulose. Labeled vegan, gluten free and GMO free Directions: 2 capsules 30 to 60 minutes before bed, or at another time of day, per Momentous Medication caution: Momentous says to check with your doctor first if you take diuretics, antibiotics or bisphosphonates
Exact variant	90 vegetarian capsules (SKU KA202599-90), 120 mg magnesium as magnesium glycinate per capsule	60 capsules (30 servings)
Dimensions	Not stated by the manufacturer. Klean's page gives 90 vegetarian capsules per container, but no bottle size, net weight or capsule size. NSF's listings give a package size of 90 and a serving size of 1 capsule.	Momentous doesn't state the bottle's dimensions. Momentous's online store lists a weight of 3.0 oz (85 g) for the 60-capsule bottle.
Installation	No installation. Klean's label says adults take 1 capsule, 1 to 4 times daily, or as a trainer, coach or health professional directs. The label doesn't mention food, but Klean's 2020 data sheet says to take it with a meal. The label says to use it only if the safety seal is intact and to store it in a cool, dry place.	No installation. Momentous's directions are 2 capsules 30 to 60 minutes before bed, or at another time of day.
Materials	Each capsule holds 120 mg of magnesium as magnesium glycinate, which the label lists as 29% of the Daily Value. The other ingredients are hydroxypropyl methylcellulose (the vegetarian capsule) and ascorbyl palmitate. Klean's page shows gluten free, GMO free, vegan and vegetarian icons. The label has no allergen statement. Klean doesn't name the magnesium's source or say what the bottle is made of. The label says it's manufactured for Klean Athlete, Pittsburgh, Pennsylvania.	The magnesium is magnesium bisglycinate, which Momentous says is chelated to glycine, an amino acid. It doesn't name the supplier. The Supplement Facts image lists hypromellose, silica, magnesium stearate and microcrystalline cellulose as the other ingredients. The label is marked vegan, gluten free and GMO free, and NSF's listing carries the same free-of claims. Momentous doesn't state what the bottle is made of.
Warranty	Klean gives no warranty term, per its return policy. The policy says Klean guarantees quality, purity and potency through the expiration date.	Not stated by the manufacturer. The product page shows a "30 day money back guarantee" with no terms, and the refund policy mentions none.
Returns	30 days from receipt, with preauthorization and a 15% processing fee plus shipping. Klean's return policy says claims of shortage or damage must be made within 7 days of receiving the package. Authorized returns must reach Klean within 14 days of authorization. Returns are credited on receipt, less the 15% fee and the cost of shipping. The policy doesn't say whether an opened bottle qualifies.	Momentous's refund policy says it generally doesn't accept returns of delivered products, except where the law requires it. Original and return shipping costs aren't refundable either, with the same exception. The policy doesn't limit your rights under consumer protection laws, and it asks you to contact Momentous if there's a problem. It gives no return window. If you bought from a retailer, the policy says to contact that retailer.
Unresolved questions	Which NSF entry a given bottle's lot number sits in, and the certification date, which neither entry shows Whether the page's retail price applies to every buyer, since it asks you to log in Whether an opened bottle qualifies for return Who makes the magnesium glycinate and where it comes from Klean's bottle size and net weight Whether Klean's current directions call for a meal, since only its 2020 data sheet says so Whether the page's description means 120 mg of magnesium or of the glycinate compound, since the label panel says magnesium	Who supplies the magnesium bisglycinate: Momentous doesn't name a source Bottle dimensions and material Which magnesium form the insomnia analysis Momentous cites covered

These comparisons use published specifications, not head-to-head tests. Prices and terms are dated. Unknown costs are not zero. Check the exact variant before you buy.