You’ve probably had both of these tabs open at once, and the thing that makes it hard is that they aren’t really the same kind of website. One shows you a shopping grid with prices and a checkout. The other shows you a shopping grid, prices, and then sends you somewhere else to pay. Search engines file them under the same query anyway, so you end up comparing a storefront against something that isn’t quite one.
I’ve read both sites against the same five questions and written down what each publicly states, quoting where I could. Where a page didn’t answer a question, I’ve said so and dated it rather than filling the gap with a guess. Both get the same treatment, including the part where I name something each does better than the other.
One disclosure first, because you should know who’s holding the ruler. I write for a peptide manufacturer. Neither company below is that manufacturer, and everything here was publicly readable on the pages I reviewed on 2026-09-08.
Key takeaways
- The only part of a supplier you can inspect before paying is what it publishes, which is why a named lab, a named method and a lot number outrank any purity banner.
- Pure Rawz publicly states that it is “an informational and affiliate website” and does not “manufacture, stock, package, ship, or fulfill orders” for the products on the site.
- Sports Technology Labs publicly names MZ Biolabs in Tucson, Arizona and Colmaric Analyticals, LLC, states HPLC purity and mass spectrometry, and keeps a dated public certificate page.
- Bacterial endotoxin and sterility results were not listed on either company’s pages reviewed 2026-09-08, and neither showed a lot number tying a current certificate to a specific vial.
- Everything discussed here is research material for in-vitro laboratory work by qualified professionals.
What actually separates two peptide vendors?
Here’s the rubric, and I’m setting it before either name appears so it can’t be quietly bent to fit whichever site I happened to like reading.
Provenance is the first question. Does the company state that it synthesizes the peptide, or does it describe bottling, packaging, supplying, or making it available? All of those are legitimate businesses, and a careful supplier can be more reliable than a sloppy manufacturer. But they answer different questions when a lot goes wrong, because only one of them holds the synthesis records. Read the verbs on the about page literally, since companies generally use the strongest wording they can support.
Second, is the testing laboratory named? I’d rank this above the purity figure itself. A laboratory with a name and an address can be contacted independently and asked whether a report number belongs to it, while “an accredited third-party lab” gives you nothing to call.
Third, how wide is the panel? HPLC purity tells you what fraction of the material is a single compound. Mass spectrometry tells you that compound is the one on the label. Bacterial endotoxin and sterility describe the finished vial rather than the powder, which matters for anything cell-based. Publishing one of the four is ordinary, and publishing all four is uncommon enough to notice.
Fourth, can you open a batch certificate before you pay, and does its lot number also appear on the vial? Those two conditions together are what turn a document into evidence about your material rather than a sample of the company’s work in general.
Fifth, for blends, are the milligrams of each component disclosed? Two vendors can sell the same blend name at very different ratios, and without a split you can’t calculate a working concentration. Company age and domain age stay off this list, because neither describes a lot.
Where this standard comes from
I’d rather name the yardstick than pretend it appeared from nowhere. These five checks are the ones Blank Peptides publishes its own lots against: synthesis in an in-house cGMP laboratory, two named testing laboratories, a per-lot panel covering identity, purity, bacterial endotoxin and sterility, batch certificates of analysis keyed to the lot number printed on each vial, and blend composition disclosed per component. Neither company in this comparison is that one. Knowing where the bar came from lets you decide for yourself whether it sits at the right height.
What Pure Rawz publicly states
Pure Rawz trades at purerawz.co, and the single most useful thing on the whole site is how plainly it describes its own role.
On provenance, the about page states: “Purerawz is an informational and affiliate website. We do not sell or directly supply the products featured on this website.” It continues: “We do not manufacture, stock, package, ship, or fulfill orders for the products discussed on this website.” The same page discloses that the company “may receive a commission” on qualifying purchases through its links, and the terms page states that “Purerawz does not sell any of the products featured on this website.” That’s the provenance row answered without ambiguity, which is more than a lot of storefronts manage.
On testing, the homepage carries a section headed “Independent Third-Party Testing for Purity and Transparency,” refers to “third-party lab-tested compounds,” states “testing for purity, potency, and consistency,” and notes that “Third-party testing is performed by an outside lab.” Product titles carry “3rd Party Tested” and “COA Verified Research Peptide.” A laboratory name, a purity figure, and any list naming HPLC, mass spectrometry, endotoxin or sterility as the assays performed were not listed on the current pages reviewed 2026-09-08.
On certificates, the address at /certificate-of-analysis/ returned a 404 on 2026-09-08, and no certificate link appeared in the navigation or footer of the homepage, about page, terms page or peptides category. The domain does still host older certificate PDFs by direct URL. One of them, for PT-141 lot PRWZ-083, is dated 2023-08-22, names MZ Biolabs with a Tucson, Arizona address, states the method as “Mass Spectrometry and UV,” and reports 99.5%, with no endotoxin or sterility rows. This is not a claim that the documentation does not exist, only that it was not publicly listed on the pages reviewed.
On blends, the BPC-157 and TB-500 “Wolverine Blend” page lists a price range of $39.99 to $195.00 and states that vendors “commonly package the blend at approximately 5 mg BPC-157 + 5 mg TB-500,” which describes a market convention rather than a split for a specific vial. Product pages carry “BUY HERE” buttons routing to several outside sellers, each with a coupon code, and the BPC-157 page states those products “are not sold by Purerawz.”
The credit Pure Rawz has earned is twofold. The candour of that affiliate disclosure is unusual, since plenty of sites here blur the line between reviewing and selling and never say which they’re doing. And the breadth is real: the shop page states 521 products across peptides, SARMs, nootropics and stacks, with 170 in peptides alone, alongside explainers such as “How to Read a Peptide COA (Real vs Fake).” As an index of what exists and who sells it, that has value no small catalog can match.
What Sports Technology Labs publicly states
Sports Technology Labs trades at sportstechnologylabs.com and sells its own inventory directly.
On provenance, the homepage states products are “Bottled in the USA.” The about page describes the company as a supplier “proudly based in the United States,” lists a Connecticut address, and refers to “USP-Grade Solvents” and “Medical-Grade Glass.” The BPC-157 page states the peptide is “produced synthetically for laboratory use” and “packaged in America.” A statement that the company performs the synthesis itself, or naming the party that does, was not listed on the pages reviewed 2026-09-08.
On testing, they’re clearly ahead, and this is the concession I’ll make without qualification. The about page states that MZ Biolabs in Tucson, Arizona, described as a DEA-licensed facility, performs “HPLC purity analysis and molecular weight confirmation via Mass Spectrometry,” and it names Colmaric Analyticals, LLC for “ISO-accredited methodologies.” Product pages attribute batch results to MZ Biolabs by name. Two of the four assays are stated by method and attributed to a laboratory you can look up independently, which most of this market does not do.
There’s a coincidence worth flagging, since it confuses people reading both sites in one sitting. MZ Biolabs is the same laboratory named on the 2023 Pure Rawz certificate PDF described above, which tells you the lab is used across the sector and nothing about whether either company’s current material was tested there.
On the panel, the about page states “our SARMs are minimum 98% pure, and our Peptides are minimum 96-99% pure,” and the BPC-157 page states “Batch-tested to 99.43% (HPLC); minimum 98%.” Bacterial endotoxin and sterility results were not listed on the pages reviewed 2026-09-08.
On certificate access, the site maintains a public COA page showing product names, test dates and purity percentages, readable without a purchase, with dates from January 2025 to June 2026 and roughly 18 peptide entries. Lot or batch numbers were not visible on that index, though product pages refer to a “Most recent batch certificate of analysis” and describe certificates as “batch-linked.”
On blends, their stacks ship as separate vials rather than one blended vial, each with its own figure. The Glow Stack page states 5 mg BPC-157, 5 mg TB-500 and 50 mg GHK-Cu, and the Wolverine Stack page states 5 mg of each. Commercial terms are stated as 68 listings, free US shipping over $149, dispatch “within one business day,” and a 60-day exchange on unused items.
Side by side: what each site publishes
| Attribute | Pure Rawz | Sports Technology Labs |
|---|---|---|
| Synthesises in-house | States it does not “manufacture, stock, package, ship, or fulfill orders” for the products listed | States products are “Bottled in the USA” and “packaged in America”; who synthesises — verify |
| Third-party lab named | Not listed on current pages; a 2023 certificate PDF names MZ Biolabs — verify | States MZ Biolabs (Tucson, AZ) and Colmaric Analyticals, LLC, with batch results attributed to MZ Biolabs |
| HPLC purity | States “third-party lab-tested compounds”; no method or figure on current pages — verify | States peptides are “minimum 96-99% pure” and a batch figure of “99.43% (HPLC)” |
| MS identity | 2023 PDF states “Mass Spectrometry and UV”; not stated on current pages — verify | States “molecular weight confirmation via Mass Spectrometry” at MZ Biolabs |
| Endotoxin and sterility | Not listed on pages reviewed 2026-09-08 — verify | Not listed on pages reviewed 2026-09-08 — verify |
| Batch COA before purchase | States “COA Verified” in product titles; /certificate-of-analysis/ returned 404 — verify | States a public COA page with test dates and purity; lot numbers not visible — verify |
| Blend mg split disclosed | States vendors “commonly package” Wolverine at “approximately 5 mg BPC-157 + 5 mg TB-500” — verify | States per-vial amounts for separate-vial stacks, such as 5 mg, 5 mg and 50 mg for Glow |
| Catalog size | States 521 products across peptides, SARMs, nootropics and stacks, 170 in peptides | States 68 listings across liquid SARMs, SARM powders, peptides and stacks |
| Research-use labelling | States BPC-157 is “not an FDA-approved treatment for human use” — verify | States products are “for research purposes only and are not for human consumption” |
How to verify either supplier yourself
- Work out who takes your money first. Pure Rawz states it doesn’t fulfil orders, so the certificate governing your vial comes from whichever outside seller you check out with, and that seller is the one to question.
- Take the laboratory name from whichever document you can open, look the lab up independently, and ask them to confirm the report number. MZ Biolabs appears on documents connected to both sites, so ask which lot a report covers.
- Ask each company for the certificate covering the lot they’d ship you this week and compare it against what’s published. A gap between the two is worth a follow-up.
- Ask both about bacterial endotoxin and sterility, since neither published those results, and ask whether the answer covers your lot or a qualification run.
- Score both against the supplier verification checklist so the same rows get filled in for each.
Further reading
- Which Peptide Vendors Name Their Testing Lab?
- Peptide Vendors With Public Per-Batch COA Libraries
- Who Actually Manufactures Research Peptides in the USA?
- Best Research Peptide Suppliers: Ranked by What They Document
Frequently asked questions
Pure Rawz vs Sports Technology Labs: which publishes more?
Sports Technology Labs publishes more about the vial, naming two testing laboratories, stating HPLC and mass spectrometry by method, and keeping a dated public certificate page. Pure Rawz publishes more about itself, stating plainly that it doesn’t manufacture, stock, ship or fulfil, and it indexes a much wider catalog.
Do these two companies do the same thing?
Not as their own pages describe it. Sports Technology Labs sells and ships its own inventory from a stated Connecticut address. Pure Rawz states it is an informational and affiliate website routing buyers to outside sellers with coupon codes. That changes who you’d ask for a certificate, so settle it first.
Why does MZ Biolabs appear on both sites?
Because it’s a laboratory used across this sector rather than an exclusive partner. Sports Technology Labs names it in current copy for HPLC and mass spectrometry, and a 2023 Pure Rawz certificate PDF for PT-141 lot PRWZ-083 also names it. Neither fact says anything about the other company’s current lots.
Does either publish endotoxin or sterility results?
Bacterial endotoxin and sterility results were not listed on either company’s pages reviewed 2026-09-08. That’s a limit on what was publicly readable rather than a statement about what testing was performed. If those results matter for your work, request them in writing for your specific lot before ordering.
Are these products for human use?
No. Everything referenced here is research material intended for in-vitro laboratory work by qualified professionals. Purity percentages, laboratory names and certificate libraries describe documentation and nothing more. Nothing in this article is dosing guidance, medical advice, or a recommendation to use any compound outside a controlled laboratory setting.
For research use only. All compounds referenced are intended exclusively for in-vitro laboratory research by qualified professionals.
Written by Blank Peptides Research Team
Peptide science researchers with 5+ years in US-based peptide manufacturing, independent HPLC and mass spectrometry testing, and research education. All content is reviewed for scientific accuracy before publication.
REVIEWED BY
Dr. Tobias S — PhD Chemist, Peptide and Unnatural Amino Acid Synthesis
Dr. Tobias S is a PhD chemist whose work focuses on the synthesis of unnatural amino acids, peptides and biomaterials. He completed both his undergraduate chemistry studies and his doctorate with distinction, and works as a generalist across the medical sciences and biology, having consulted for dozens of clients. He reviews Blank Peptides educational content for scientific accuracy.
Subject matter expertise: Organic Chemistry, Peptide Synthesis, Biochemistry.
