LookCloser.aipublic supplement evidence
Exact product checked · GTIN 00850033272215Double Wood Supplements · checked Jul 24, 2026🇺🇸 USPTO wordmark owner · Double Wood LLC · PENNSYLVANIA, USAPackage says manufactured by: Double Wood
Quick read · Double Wood Supplements

Magnesium Glycinate 400mg | 180 Capsules | Sleep

Checked against public sources on July 24, 2026 · LookCloser does not sell or recommend supplements.

Does the marketing hold up?

The barcode identity checks out · 850033272215. The barcode matches, so we are checking the right product rather than a look-alike.

Right product?Yes — barcode matched
Is the dose real?Panel read — 2 ingredients listed
Who’s behind it?🇺🇸Double Wood LLClimited liability company · PENNSYLVANIA, USA
Trouble on record?No recalls found

“Couldn’t verify” means we looked and found no public proof — not a mark against the product. Most supplement claims cannot be independently verified by anyone, so grey is the normal state of this industry.

3◖ partly confirmed1? couldn’t verifyno contradictions · no recalls
Marketing claims, checked

The checks, one by one

The public sources did not settle the marketing promises on this label.

Partly confirmed3

“than other forms such as magnesium oxide. GMP CERTIFIED Facility Manufactured in the USA”

“GMP-certified” describes factory processes, not what is in the bottle. The claim does not name a certifier or public register that a shopper can check.

Evidence →
“| 180 Capsules | Sleep, Muscle, & Heart Support | Vegan, Third Party Tested, Gluten Free,”

Published research exists for ingredients in this formula — see Related research below. Whether this product’s doses match those studies could not be confirmed.

Evidence →
“| Sleep, Muscle, & Heart Support | Vegan, Third Party Tested, Gluten Free, Non-GMO, by Double Wood”

A testing body is named on the listing, but we found no lot-specific certificate of analysis.

Evidence →

Ingredient research can support context, but it is not a trial of this exact product.

?Couldn’t verify independently1

“as magnesium oxide. GMP CERTIFIED Facility Manufactured in the USA From Globally So Third-Party Tested”

“Made in USA” can describe only final bottling. Ingredient-sourcing records were not located for this product.

Evidence →

We looked and found no public proof. That does not count against the product.

Quick read · 2 useful findings

What is worth knowing.

Headlines first. Open evidence only when you want the source trail.

Checks outWho is behind it?

The barcode identity checks out · 850033272215.

The barcode matches, so we are checking the right product rather than a look-alike.

Evidence and sources

UPCitemdb resolves 850033272215 to "Magnesium Glycinate - 180 x 400 mg capsules" (Double Wood Supplements) — consistent with this listing.

Locked evidence record →Open the full source-linked finding
What remains open 2
  • Panel amounts still need a clearer source image.
  • No matched to this exact product public label filing is saved in this record.

These are evidence gaps, not strikes against the product.

Who owns the brand wordmark?
🇺🇸
Double Wood LLCLimited Liability Company · exact supplement-class mark for DOUBLE WOOD SUPPLEMENTS
Registration5323413
Registered2017-10-31
AssignmentsNo transfers recorded

Filed address
22 Lindsey Ave, Danville, PENNSYLVANIA 17821, UNITED STATES

USPTO identifies the public owner or applicant behind this brand wordmark. This does not by itself identify the product manufacturer or prove where the product was made. Open USPTO source ↗

Research behind the findings

Dose and research context

The label amount is shown beside the ranges used in the linked ingredient studies.

Where it sells

Price check for this exact product

Amazon

Exact UPC/GTIN match
$16.99

$0.09 per labeled serving

matching UPC/GTIN · checked Jul 25, 2026

View on Amazon ↗

iHerb

Exact UPC/GTIN match
$17.95

4.6/5 · 25 ratings

$0.10 per labeled serving

matching UPC/GTIN · checked Jul 24, 2026

View on iHerb ↗

Brand website

Official product-page candidate · UPC absent
$47.41

Official shopping lead; excluded from exact price comparisons.

Magnesium Glycinate Extra Strength · Double Pack. Confirm the package UPC/GTIN before buying.

Check brand website ↗

Walmart

Not confirmed
No exact listing saved

Search results remain not linked to this exact product until this retailer publishes the matching UPC/GTIN.

Search Walmart ↗

Same UPC/GTIN observed across 2 sellers. Amazon was lowest at $16.99; iHerb was highest at $17.95 — a $0.96 range at check time.

The brand-page price is shown as a shopping lead only. It is excluded from the exact-product price difference because the page does not publish this record's matching UPC/GTIN.

Reference prices only · no affiliate links · every compared seller must publish the matching UPC/GTIN.

Want the complete evidence trail?

The summary stops at product-specific facts. The full report preserves every source, calculation, limitation, and unresolved check for review or sharing.

Read / share full evidence →

Record built July 24, 2026. Sources: source listing observed at check time · USPTO Trademark Search · Keepa exact-listing history · NIH / published research · certification and regulator records where available. LookCloser publishes evidence and gaps; it does not advise for or against any supplement. Evidence-based corrections welcome.