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    Retatrutide Pen Kit 40mg — research peptide kit
    METABOLIC≥99% HPLC ✓

    Retatrutide Pen Kit

    Retatrutide (LY3437943) — dual-chamber pen format · 40mg

    CAS
    2381089-83-2
    Mol. Weight
    4731.4 g/mol
    Sequence / Formula
    Triple agonist GIP / GLP-1 / Glucagon

    Journal · In-depth

    Read our in-depth article on Retatrutide Pen Kit — what's proven, what isn't.

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    The Retatrutide Dual-Chamber Pen Kit supplies 40mg of triple-agonist research compound in an advanced cartridge format designed to keep the lyophilised peptide powder and bacteriostatic water completely separate until activation.

    Unlike standard pre-filled liquid cartridges, the dual-chamber system stores the dry peptide powder and liquid component in separate chambers within the same cartridge. The cartridge is only mixed once placed into the compatible pen and activated, meaning the compound is not sitting pre-reconstituted in solution before it reaches you.

    This matters because lyophilised peptide powder can remain stable for significantly longer when stored correctly, while once reconstituted with bacteriostatic water the usable research window is typically much shorter. With a traditional liquid cartridge, it can be difficult to know how long the compound has already been mixed before supply.

    The PROTEUS dual-chamber format gives greater clarity and control. The compound remains separated until activation, helping preserve integrity before mixing and giving a clear starting point for the post-reconstitution research window.

    The click-dial pen format is designed for consistent, repeatable measurement without manual syringe-based reconstitution. This creates a cleaner, more controlled and more convenient format for laboratory research handling.

    Kit includes compatible pen, one 40mg dual-chamber Retatrutide cartridge, and bacteriostatic water contained within the cartridge system. Independently lab-tested at ≥99% purity by HPLC, with a third-party Certificate of Analysis available for every batch.

    Store unopened cartridge as directed, away from direct light. Once activated and reconstituted, refrigerate at 2–8°C and use within the recommended research window.

    This product is sold strictly for research purposes only. Not for human consumption, and not intended to diagnose, treat, cure or prevent any disease or condition.

    £185.00Kit incl. BAC waterSKU · RTKDC40
    Pre-order

    Stock lands 14 August 2026 — order now to reserve your kit from the incoming batch. Pre-orders ship in the order received as soon as stock arrives, approximately one week from today.

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    3ml Bacteriostatic Water vial included with kit

    BAC Water Included

    Every kit ships with a matched 3ml Bacteriostatic Water vial for reconstitution — no separate purchase required.

    Research Use Only

    For laboratory and research use only. Not for human or animal consumption, in vivo use, food, drug, household or cosmetic use. Not intended to diagnose, treat, cure or prevent any disease.

    Proteus twin protective case — peptide and BAC water vial

    Twin Case

    Proteus full kit — sealed tear-open bag, twin case and both vials

    Full Kit

    What's in the box

    Everything included.

    Every order includes BAC water for reconstitution — no separate purchase needed. Your kit arrives in a sealed, tamper-evident bag containing a protective twin case holding your peptide vial and BAC water vial, ready to use.

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    All products sold by Proteus® are strictly for research purposes only. Not for human consumption. Not intended to diagnose, treat, cure or prevent any condition. Sold as research chemicals only.

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    Research Disclaimer

    Proteus® products are research chemicals supplied to qualified researchers, laboratories, and institutions in the United Kingdom. Not for human consumption. Not for diagnostic or therapeutic use. By purchasing, you confirm research-only intent.

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