S4 and Cardarine Stack

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/* ———- COA IMAGE ———- */
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Why this bundle

Key highlights

Two-bottle research bundleOne 30 mL bottle each of S4 and Cardarine, supplied together at a bundle discount.

50 & 20 mg/mLS4 at 50 mg/mL (1,500 mg) and Cardarine at 20 mg/mL (600 mg), each with under 5% variance.

Independently verifiedEach compound is HPLC-tested by an accredited US third-party lab for purity and identity.

Research use onlySupplied exclusively for laboratory investigation and development.

Technical data

Andarine (S4)99.74% pure

Cardarine (GW-501516)99.57% pure

See all certificates of analysis

Why source this stack from Sports Technology Labs

Quality control across the research-compound industry is inconsistent, which makes third-party verification essential. A 2017 analysis published in JAMA examined 44 products marketed online as SARMs and reported wide gaps between labels and contents.

52%contained the labeled compound
39%contained an unapproved drug
25%contained an unlabeled substance
9%contained no active ingredient

Source: Van Wagoner et al., JAMA, 2017 (ref. 3).

Third-party tested & certified

Both compounds verified by MZ Biolabs (Tucson, AZ), an accredited US laboratory, via HPLC and mass spectrometry.

USP-grade PEG-400

Suspended in the highest grade carrier and bottled in America.

Glass bottles, fixed glass droppers

Prevents BPA leaching and avoids contamination from external tools.

60-day money-back guarantee

Transparent business, standard payment methods, no misrepresentation.

Research context

What is in this stack?

Component 1

Andarine (S4)

A non-steroidal selective androgen receptor modulator (SARM). Mechanistically, it binds the androgen receptor with tissue-selective affinity, distinguishing it from steroidal androgens. It was developed as an investigational compound through programs associated with GTx, Inc. (ref. 1).

Component 2

Cardarine (GW-501516)

A synthetic PPARδ (peroxisome proliferator-activated receptor delta) agonist. Mechanistically, it binds and activates the PPARδ nuclear receptor. Although commonly catalogued and sold alongside SARMs, it is mechanistically distinct and does not bind the androgen receptor (ref. 2).

Both compounds remain experimental research chemicals, supplied strictly for laboratory research. Sports Technology Labs makes no claims regarding their effects, and nothing in this listing should be interpreted as describing outcomes in humans or animals.

Regulatory & compliance status

Scientific references

1. Narayanan R, Mohler ML, Bohl CE, Miller DD, Dalton JT. Selective androgen receptor modulators in preclinical and clinical development. Nucl Recept Signal. 2008;6:e010.
2. Oliver WR Jr, et al. A selective peroxisome proliferator-activated receptor delta agonist promotes reverse cholesterol transport. Proc Natl Acad Sci USA. 2001;98(9):5306–5311.
3. Van Wagoner RM, et al. Chemical composition and labeling of substances marketed as SARMs and sold via the internet. JAMA. 2017;318(20):2004–2010.
4. WADA Prohibited List (2025), Sections S1 (Anabolic Agents — SARMs) and S4 (Hormone and Metabolic Modulators). WADA.org.

Research use only. All products on this website are intended exclusively for laboratory research and development. They are not for human or animal consumption. These statements have not been evaluated by the U.S. Food and Drug Administration, and these products are not intended to diagnose, treat, cure, or prevent any disease.