Why Oxymetholone instead of Methandienone as a kick-start?

Oxymetholone delivers the strongest initial anabolic effect of any oral compound, but places a heavier burden on the liver. For less aggressive protocols see our Nordi Mass Protocol.

Is 350 mg/ml more painful to inject?

Higher concentrations can cause stronger PIP (post-injection pain). Warming vials to body temperature and injecting slowly reduces this noticeably.

How much mass is realistic in 10 weeks?

With a +400–600 kcal surplus and progressive training, total mass gains of 7–11 kg are typical, of which 3–5 kg generally remain after water loss.

Do I need Cabergoline because of Nandrolone?

Keep it on hand and use it only if elevated Prolactin is confirmed by blood work with symptoms present. Have Prolactin tested at week 5.

Due to the Decanoate half-life of 6–7 days, begin PCT no earlier than 4 weeks after the last injection.

Concentrex Bulk Protocol – EnanTrex 350 + DecaTrex 350 + OxyTrex 25mg

High Concentration

Wuchs Stacks

Concentrex Bulk Protocol – EnanTrex 350 + DecaTrex 350 + OxyTrex 25mg

Name: Concentrex Bulk Protocol – EnanTrex 350 + DecaTrex 350 + OxyTrex 25mg
Brand: Wuchs Stacks
SKU: STACK-CBULK-01
Price: 216.00 EUR
Availability: InStock

Concentrex Bulk Protocol is a 10-week mass bundle containing 2× EnanTrex 350 (Testosterone Enanthate), 2× DecaTrex 350 (Nandrolone Decanoate) and 1× OxyTrex 25 mg (Oxymetholone) at a high 350 mg/ml concentration.

€216.00Free shipping on orders over €300

In stock

Ships within 48 h Lab-tested batch

350 mg/ml concentration: only 2 ml of Testosterone per week instead of 2.8 ml with a standard 250 mg product
Nandrolone Decanoate increases collagen synthesis and protects joints under heavy loads
Oxymetholone delivers the strongest oral kick-start of any commonly used compound
Uniform Concentrex batches: reproducible concentration across all vials
10-week protocol with a dosing table included with the shipment

Phase	Week	EnanTrex 350	DecaTrex 350	OxyTrex 25mg	Note
Kick-start	1–4	700 mg/wk (2× 1 ml)	525 mg/wk (2× 0.75 ml)	50 mg/day	Check liver values before starting
Building	5–8	700 mg/wk	525 mg/wk	–	Measure blood pressure 2×/wk
Finishing	9–10	700 mg/wk	525 mg/wk	–	Monitor haematocrit
Taper	11–14	–	–	–	Begin PCT after Decanoate half-life

Key takeaways

Use the 350 mg concentration for minimal injection volume
Kick-start with Oxymetholone for rapid mass gains
Benefit from Nandrolone's joint protection during heavy bulking
Receive 5 matched products in one coordinated bundle
Save 10 % compared to buying each component separately

Concentrex Bulk Protocol is a pre-configured mass-building stack comprising 2× EnanTrex 350, 2× DecaTrex 350 and 1× OxyTrex 25 mg – an exclusively Concentrex Labs bundle at high concentration, designed for a 10-week bulk phase.

The Advantage of the 350 mg Concentration

Standard formulations deliver 250 mg/ml; Concentrex doses at 350 mg/ml, which is 40 % higher. At a weekly dose of 700 mg Testosterone this means 2 ml instead of 2.8 ml injection volume – fewer injection-site rotations, less connective-tissue stress and better compliance over 10 weeks.

The Classic Bulk Triad

Testosterone Enanthate forms the foundation; Nandrolone Decanoate adds collagen synthesis and joint protection – a noticeable advantage under heavy compound lifts. Oxymetholone (50 mg/day in weeks 1–4) is the most aggressive oral kick-start available: pronounced cell volumisation and erythropoiesis within the first 10 days, while the depot esters are building up.

Who This Stack Is For

Experienced athletes with at least three completed cycles who are targeting maximum overall mass within 10 weeks and who can manage the demands of Oxymetholone (liver, blood pressure, water retention). Not suitable for beginners or anyone with liver disease – see warnings.

Usage

Obtain a full blood panel including liver values and lipids before week 1.
Inject EnanTrex and DecaTrex intramuscularly every Monday and Thursday.
Take OxyTrex in weeks 1–4 split across 2 doses per day (morning and early afternoon).
Drink at least 3 litres of water daily – Oxymetholone places significant demand on fluid balance.
Begin PCT no earlier than 4 weeks after the last injection, accounting for the Decanoate half-life.
After completing PCT, observe a rest period of at least cycle length plus PCT length before the next cycle.

Warnings

Contraindications

Do not use in cases of prostate or breast carcinoma, liver disease of any kind, severe renal insufficiency, pregnancy, breastfeeding or in individuals under 18 years of age. Oxymetholone is among the most hepatotoxic oral anabolic agents available – for experienced users only.

Side Effects

Oxymetholone can significantly elevate liver enzymes, worsen water retention and raise blood pressure, and may trigger oestrogenic side effects without aromatisation. Nandrolone can affect libido via Prolactin. HDL reduction and acne are to be expected.

Monitoring

Check liver values (ALT, AST, GGT) weekly during the Oxymetholone phase; discontinue the oral component if values double from baseline. Full blood count including haematocrit at week 5. Self-measure blood pressure twice weekly.

PCT

Due to the Decanoate half-life of 6–7 days, begin no earlier than 4 weeks after the last injection: Tamoxifen 20 mg/day plus Clomiphene 50 mg/day for 4–6 weeks. See our Concentrex PCT Protocol as a ready-made bundle.

Frequently asked questions

Why Oxymetholone instead of Methandienone as a kick-start?: Oxymetholone delivers the strongest initial anabolic effect of any oral compound, but places a heavier burden on the liver. For less aggressive protocols see our Nordi Mass Protocol.
Is 350 mg/ml more painful to inject?: Higher concentrations can cause stronger PIP (post-injection pain). Warming vials to body temperature and injecting slowly reduces this noticeably.
How much mass is realistic in 10 weeks?: With a +400–600 kcal surplus and progressive training, total mass gains of 7–11 kg are typical, of which 3–5 kg generally remain after water loss.
Do I need Cabergoline because of Nandrolone?: Keep it on hand and use it only if elevated Prolactin is confirmed by blood work with symptoms present. Have Prolactin tested at week 5.
When do I start PCT?: Due to the Decanoate half-life of 6–7 days, begin PCT no earlier than 4 weeks after the last injection.

Manufacturer

Concentrex Bulk Protocol is curated by wuchs.net as an exclusively Concentrex Labs bundle: EnanTrex 350, DecaTrex 350 and OxyTrex all originate from the same batch-controlled production line at 350 mg high concentration. The composition follows the 10-week protocol set out in the dosing table.

Product details

Brand	Wuchs Stacks
Also known as	Concentrex Bulk Stack, Test Deca Anadrol Stack, Masseaufbau Bundle Concentrex
Form	bundle
Item number	STACK-CBULK-01

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