GE Labs and MonsterKing: the SARM brand whose Ykarine held an undeclared steroid, and the company behind both stores

Who they are, and what the record says

GE Labs, "Genetic Engineering Laboratories", is a supplement brand. MonsterKing is the web store that sells it, alongside some sixty-five other brands, in more than a dozen language versions. The FDA treats them as one business. Its warning letter of 12 December 2025 is addressed to "Musclepower Enterprise Ltd. dba MONSTER KING and GE LABS", at a street address in Madison, Wisconsin, with three email addresses on the two stores' domains and Gmail.[1]

Figure 1. 12 December 2025. The FDA's letter names one company, two trading names and two websites, and says it bought the products in March. [1]

The stores name their seller in their terms, and the name has changed. In June 2021 MonsterKing's terms named "Muslcepower Trading Ltd, 2 Pass Street , Oldham, Manchester, OL9 6HZ, UK Company number: 11071140", represented in Slovakia, the Czech Republic, Poland and Hungary by an organizational unit with a Slovak identification number. The same paragraph says that unit "does not sell any goods or services to the end customer" and serves for communication.[2] By March 2025 the terms named the seller as "Muslcepower Enterprise LLC, WI , USA", and the GE Labs store's terms said the same.[3][4] The misspelling "Muslcepower" is the stores' own, and the registers'.

The English company is on the record. Companies House lists company 11071140 as active, incorporated on 20 November 2017 as Trade & Commerce Enterprise Limited and renamed in September 2018, at "Enterprise House, 2 Pass Street, Oldham, Manchester, United Kingdom, OL9 6HZ", in "46900 - Non-specialised wholesale trade".[5] Its first accounts, to 30 September 2018, were filed as a dormant company. In September 2024 Companies House published a "First Gazette notice for compulsory strike-off"; the next month accounts were filed and the strike-off was discontinued.[6] Since 14 September 2018, the day of the renaming, its person with significant control has been a resident of Slovakia holding "Ownership of shares – 75% or more".[7]

Figure 2. The company the store's terms named in 2021: Muslcepower Trading Ltd, England, incorporated 2017 under another name. [5]

The Slovak unit is on the record too. The Slovak commercial register entered "Muslcepower Trading Ltd. - organizačná zložka", a branch of a foreign company, on 20 December 2018, at an address in Bratislava's Karlova Ves district, identification number 52086666. Its registered activities are retail and wholesale trade, light road haulage, courier services, fast food, business consulting and advertising.[8][9] The register names the same Slovak resident as head of the branch.

Figure 3. The branch in Bratislava, registered December 2018. The extract continues with its head and the UK parent; we cropped it above the personal details. [8]

Figure 4. June 2021: the store names its seller, the English company and its Slovak unit, by number. [2]

We found no register entry for Musclepower Enterprise under either spelling. Companies House returns only the Oldham company for Muslcepower and no company named Musclepower Enterprise; the Slovak register returns only the branch.[5][8] The FDA letter's "Ltd." and the stores' "LLC, WI" do not resolve, in what we searched, to a registration. The stores themselves look Slovak: the GE Labs store in October 2023 called the brand "GE LABS, USA", priced in dollars, and had a search box labelled in Slovak.[10]

Figure 5. October 2023. "GE LABS, USA", prices in dollars, a Slovak search box, and categories for prohormones (PH) and SARMs. [10]

Figure 6. The company and its two stores, 2017 to 2026. Drawn by us from the registers, the archived pages and the FDA's documents. [5]

MonsterKing's first archived capture is from December 2020; GE Labs' is from December 2021. The archive holds 1,854 MonsterKing pages and 235 GE Labs pages; the latest captures are from October and July 2026.[11][12]

What they sell

SARMs. In April 2025, a month after the FDA bought its samples, the GE Labs SARMs category listed more than twenty GE Labs products and sets, among them Ostarine, Andarine Max, LGD, RAD-150, S-23, MK 677, Ykarine and Ykarine Pro.[13] The Ykarine Pro page described a "GE Labs Ykarine Pro - formulation based on SARM YK-11", and said Ykarine "does not lead to classic side effects attributed to the group of androgens". Of the NAC in it, the page said: "NAC binds and excretes toxic metabolites from the body when steroids pass through the liver".[14] We read the labels of Ykarine and Ykarine Pro only. The other products are listed here by the names the store gave them.

Figure 7. April 2025, a month after the FDA's purchase: Ykarine, Ykarine Pro and MK 677 in the store's SARMs category. [13]

Figure 8. Ykarine Pro, April 2025: "formulation based on SARM YK-11", with a no-side-effects claim for the androgen it names. [14]

Prohormones. The store's "PH" category in April 2025 listed products named Tren, Tren Max, DBOL-X, DMZ, Massdrol, Power Drol, Primo 25, VAR 20, Epi-GH, EPI 20 and Epimax 20.[15] In May 2026 the GE Labs store, in its United States version, sold Epimax 20: "EPIMAX 20 (Epistane) is a prescription strength Pro-Anabolic Mass builder", and "EPIMAX 20 has minimal side effects". Its label gives the active compound a chemical name that begins "2,3a-epithio-17a-methyletioallo", and its directions begin "As a dietary supplement".[16] The Designer Anabolic Steroid Control Act of 2014 lists, among the compounds it adds to the definition of an anabolic steroid, "2a,3a-epithio-17a-methyl-5a-androstan-17b-ol".[17] We set the two names side by side. We found no document that rules on this product. The deep dive on designer steroids tells the history of that Act.

Figure 9. May 2026, on the US version of the GE Labs store: Epimax 20, "(Epistane)", on a Supplements Facts panel. The menu's SARMs tab is gone; Special Ingredients has taken its place. [16]

Stimulants. The GE Labs store sold DMAA XT60, "a supplement with a very strong stimulating effect", and "DMAA XT60 provides a high dose of geramine, which is also known as 1,3 Dimethylamylamine (DMAA)".[18] It also sold a DMHA product, "a strong stimulant with a similar effect to DMAA".[19]

Figure 10. DMAA XT60 on the GE Labs store, November 2025, in its Nootropic category. [18]

Other brands. MonsterKing resells other brands' products, among them Blackstone Labs, USP Labs and Hi-Tech Pharmaceuticals. Two days after the FDA's letter, MonsterKing's SARMs category held Hi-Tech's Osta-Plex, "Legal Gear (SARM) for Competitive Athletes".[20] In April 2026 it listed Hi-Tech's Dianabol, a "Natural Steroidal Anabolic and Anti-Proteolytic Formulation", under Special ingredients.[21] Hi-Tech has its own dossier.

Payment and shipping. In 2025 both stores took cards ("filling in the card number, card expiration time, and CVV code") and bank transfer, and shipped by courier to the "United Kingdom, USA, all countries Europe Union and Croatia". Outside the EU, "all shipments are subject to customs clearance".[22] When a card order is cancelled, the terms say "a fee for returning the amount for the order up to 10% is charged from the amount paid for the order".[4]

Figure 11. April 2025: card or bank transfer, courier to the US, the UK and the EU. [22]

What buyers report

We searched r/sarmssourcetalk, r/SARMs, r/PEDs and r/Supplements on 2026-10-12 through the Arctic Shift archive, for "monsterking", "ge labs" and "ykarine". Seven threads named one of the stores, from 2023 to 2026.[23] All seven are questions. In 2024 a buyer wrote that friends had recommended the store "but it just seems sketchy for me".[24] In 2025 a thread asked which sources to avoid, opening "Trying to avoid getting scammed or underdosed stuff", and named MonsterKing among stores with mixed reports; no reply described an order from it.[25] A 2026 thread asked whether GE Labs was genuine and got no answer about the brand.[26] We found no first-hand report of an order, good or bad, and no buyer's test.

Lab results

In 2023 the GE Labs store said its "quality raw materials supplied are laboratory tested and subjected to spectrometric tests and tests".[10] We found no certificate of analysis on any product page we read, from 2025 to 2026.[14][27] This site's lab-results section holds no test of a GE Labs product.

The one test on record is the FDA's. "An FDA laboratory recently tested GE Labs Ykarine". The agency's letter says the sample "contains undeclared trendione (estra-4,9,11-triene-3,17-dione), which is an anabolic steroid and is classified as a schedule III-controlled substance by the U.S. Drug Enforcement Administration (DEA)".[1] The FDA's page adds: "The laboratory analysis also confirmed the product contains YK-11, which is a listed ingredient on the product label". The FDA's reason for testing: "The agency testing was based on an adverse event report of a consumer who used the product and subsequently suffered a stroke".[28] Trendione, as "Estra-4,9,11-triene-3,17-dione", is one of the compounds the 2014 Act named.[17]

Figure 12. The FDA's page, December 2025: the bottle it tested, and what its laboratory found in it. [28]

Regulatory and legal

The FDA, December 2025. The letter says the FDA reviewed the two stores "between March and November 2025", and that "in March 2025, FDA obtained samples of" Ykarine and MK 677 through MonsterKing. It found the products marketed as SARMs to be unapproved new drugs ("these products are unapproved new drugs"), and Ykarine misbranded because "the label does not declare that the product contains trendione". It also rejected both labels' dietary-supplement claims on their other ingredients: "NAC products are excluded from the dietary supplement definition", and "ibutamoren is excluded from the definition of a dietary supplement".[1] As evidence of drug use it quoted the companies' own pages and packaging: "MYOSTATIN INHIBITOR", "INCREASE MUSCLE MASS", and for MK 677, "MK 677 IBUTAMOREN acts as an orally active GH secretagogue".[1]

Figure 13. The claims the FDA quoted as evidence that these are drugs, from both websites and the outer packaging. [1]

On risk the letter says: "life-threatening reactions, including liver toxicity, have occurred in people taking products containing SARMs", "SARMs also have the potential to increase the risk of heart attack and stroke", and "anabolic steroids can cause serious liver injury and life-threatening reactions such as kidney damage, heart attack, stroke, pulmonary embolism, and deep vein thrombosis".[1] The FDA's consumer page: "The agency urges consumers not to use GE Labs Ykarine". "Consumers who have this product should discard it".[28]

The letter notes that the two products "appear to no longer be available for sale in the United States through your website", and adds that "it is essential that these violations do not recur". It closes: "Failure to adequately address this matter may lead to regulatory or legal action including, without limitation, seizure and injunction".[1] We found no published response and no close-out letter.

After the letter. In April 2026 MonsterKing's category "Special ingredients for research - not for human or animal consumption" listed GE Labs Ykarine and Ykarine Pro as on stock, with the other GE Labs SARMs and several MK 677 products. "They are not approved as a dietary supplement or medicine," the header says.[29][30] The Ykarine page in May 2026 kept a "Supplements Facts" panel with a serving size and YK-11. Trendione was not on it. Below it, a notice said such products "are sold exclusively for laboratory and scientific research use" and "These products are not intended for human or animal consumption, are not dietary supplements, medicines, or veterinary products".[27] The page that day also marked the product "Temporarily unavailable".

Figure 14. April 2026, four months after the letter: the same SARMs, Ykarine among them, now under "Special ingredients" for research. [29]

Figure 15. May 2026: a Supplements Facts panel with a serving size, above a notice that the product is not for human consumption. Trendione is not on the panel. [27]

Still open

• Musclepower Enterprise as a company. Searched Companies House by name and the Slovak register of legal persons; neither holds a company of that name. The Wisconsin and Hong Kong registers were not searched.
• Who makes GE Labs products. The 2023 store said "GE LABS, USA is a hardcore brand manufactured by the pharmaceutical company NutraScience Labs, USA".[10] We found no document from any manufacturer naming GE Labs.
• What was in the other GE Labs products. No test of any GE Labs product other than Ykarine was found, in the FDA's records or on Reddit.
• A response to the FDA. Searched the FDA's warning-letter index for the company and both trade names; one letter, no close-out.

Changes

• 2026-10-12: first published.

References

1. FDA warning letter to Musclepower Enterprise Ltd. dba MONSTER KING and GE LABS, MARCS-CMS 719339, 2025-12-12 — U.S. Food and Drug Administration
2. MonsterKing Terms and Conditions, archived 2021-06-20 — Wayback Machine
3. MonsterKing Terms and Conditions (US version), archived 2025-03-15 — Wayback Machine
4. GE Labs Terms and Conditions, archived 2025-04-27 — Wayback Machine
5. Companies House: MUSLCEPOWER TRADING LTD, company 11071140, overview — Companies House (UK)
6. Companies House: MUSLCEPOWER TRADING LTD, filing history — Companies House (UK)
7. Companies House: MUSLCEPOWER TRADING LTD, persons with significant control — Companies House (UK)
8. Slovak register of legal persons (RPO): Muslcepower Trading Ltd. - organizačná zložka, IČO 52086666 — Statistical Office of the Slovak Republic
9. Slovak commercial register (Obchodný register), Bratislava III city court, section Po, insert 5536/B — Ministry of Justice of the Slovak Republic
10. GE Labs home page, archived 2023-10-30 — Wayback Machine
11. Wayback Machine capture index for monsterking.eu: 1,854 pages, first capture 2020-12-18, last 2026-10-06 — Wayback Machine
12. Wayback Machine capture index for gelabsonline.com: 235 pages, first capture 2021-12-05, last 2026-07-12 — Wayback Machine
13. GE Labs SARMs category, archived 2025-04-27 — Wayback Machine
14. GE Labs Ykarine Pro product page, archived 2025-04-27 — Wayback Machine
15. GE Labs PH (prohormones) category, archived 2025-04-27 — Wayback Machine
16. GE Labs Epimax 20 product page, archived 2026-05-14 — Wayback Machine
17. Designer Anabolic Steroid Control Act of 2014, Public Law 113-260, 128 Stat. 2929 — US Government Publishing Office
18. GE Labs DMAA XT60 product page, archived 2025-11-18 — Wayback Machine
19. GE Labs DMHA product page, archived 2025-04-27 — Wayback Machine
20. MonsterKing, Hi-Tech Pharmaceuticals Osta-Plex product page, archived 2025-12-14 — Wayback Machine
21. MonsterKing, Hi-Tech Pharmaceuticals Dianabol product page, archived 2026-04-11 — Wayback Machine
22. GE Labs Transport and payment options, archived 2025-04-27 — Wayback Machine
23. Posts naming MonsterKing or GE Labs in r/sarmssourcetalk (4), r/SARMs (2), r/Supplements (1) and r/PEDs (0), searches 'monsterking', 'ge labs' and 'ykarine', 2026-10-12, through the Arctic Shift archive: 7 threads, 2023 to 2026 — Arctic Shift — anecdotal report, not evidence
24. SARMS in EU (2024-02-19) — r/sarmssourcetalk — anecdotal report, not evidence
25. Who's the worst SARMs source you've used? (2025-06-29) — r/SARMs — anecdotal report, not evidence
26. Smart Brothers legit ? Or GE Labs ? (2026-01-21) — r/SARMs — anecdotal report, not evidence
27. MonsterKing, GE Labs Ykarine product page, archived 2026-05-19 — Wayback Machine
28. Certain bodybuilding products put consumers at risk for heart attack, stroke, serious liver damage and more (current as of 2025-12-02) — U.S. Food and Drug Administration
29. MonsterKing Special ingredients category, archived 2026-04-10 — Wayback Machine
30. MonsterKing, GE Labs Ykarine Pro product page, archived 2026-04-11 — Wayback Machine