MASS 400

What is Mass 400?

Mass 400 is a high-strength injectable anabolic steroid blend, concentrated at 400 mg per milliliter and usually sold in a 10 ml vial, giving a total of 4,000 mg per vial. It’s made by Opal Pharma and commonly found across the UK and EU under names like “Mass 400” or “Mass 400 400 mg/ml.”

What makes it unique is the mix of several active compounds, often different testosterone esters and sometimes boldenone or trenbolone types, all combined into one powerful formula. The goal is to help build serious muscle mass, increase strength, and improve performance. You’ll often see it on UK supplement sites with phrases like “Buy Mass 400 UK” or “Mass400 Injection.”

Because of its strong concentration, Mass 400 is meant for experienced users who already have solid training, nutrition, and recovery habits. It’s not recommended for beginners.

How Mass 400 Works

Mass 400 works by delivering anabolic and androgenic compounds directly into muscle tissue through intramuscular injection. This process boosts protein synthesis, improves nitrogen retention, speeds up recovery, and supports overall muscle growth.

Its blend of esters releases at different speeds, meaning you get both fast and slow effects that keep your body in a muscle-building state for a longer period.

In simple terms, this results in:

• Faster activation of androgen receptors, which helps with strength and size gains.

• Long-acting esters that maintain steady hormone levels instead of quick spikes and drops.

• Better nutrient use, turning more of your food and training effort into lean muscle instead of fat.

Because of its potency, Mass 400 works best when your workout routine, nutrition, and rest are already well-structured.

How Long Mass 400 Lasts

Thanks to its long-acting ester components and 400 mg/ml concentration, you don’t need to inject it very often. Many users find one injection per week enough, while others prefer splitting it into two smaller doses for smoother hormone levels.

Its effects can last anywhere from 10 to 14 days or longer after each injection, depending on the esters in the formula. A typical cycle runs 8 to 16 weeks to let the compounds build up and reach full effectiveness.

Even after your last dose, some effects can linger due to the slow release of the compounds.

Dosage and Cycle Guide

With a 400 mg/ml strength, most users take between 400 and 800 mg per week based on their experience and goals. Beginners who already have some steroid experience might start at 400–500 mg weekly to test tolerance.

Mass 400 is injected deep into the muscle and often split into two injections per week, such as Monday and Thursday, to keep hormone levels balanced and reduce injection discomfort.

Cycles typically last 10–12 weeks, though some extend to 16 weeks depending on goals. One 10 ml vial provides around 10 weeks of use at 400 mg per week.

Because this product is so concentrated, proper injection technique, site rotation, sterile handling, and a well-planned post-cycle recovery are all crucial.

Side Effects and What to Watch For

Mass 400 is powerful, and with that strength comes potential side effects. Like any anabolic steroid, risks increase with higher doses or longer cycles.

Possible side effects include:

• Estrogenic effects such as water retention, high blood pressure, and gynecomastia (male breast tissue growth) depending on the testosterone content.

• Androgenic effects like acne, body or facial hair growth, and possible hair loss if genetically prone.

• Cardiovascular strain due to changes in cholesterol levels and added pressure on the heart.

• Hormonal suppression, as natural testosterone production will decrease and require proper post-cycle therapy.

• Liver and kidney stress, especially with long-term or high-dose use.

• Injection site pain, which is common with concentrated formulas like 400 mg/ml. Splitting doses or diluting can help ease discomfort.

Since Mass 400 includes multiple active compounds, side effects can overlap or intensify. Always monitor your body closely and take your recovery seriously.

Things to Consider Before Buying or Using

If you’re planning to buy Mass 400 in the UK, make sure it’s genuine. Check that the label, manufacturer (Opal Pharma), and batch numbers are correct.

This product isn’t for first-timers. It’s intended for advanced users who understand steroid use and already have consistent training, diet, and recovery habits.

Plan your cycle, dosage, and post-cycle recovery before you start. Store the vial correctly in a cool, dark, clean place and check for clarity or any unusual signs before injecting. Need help with the dosage? Contact Medicine4Me to get advices :)

It’s also important to understand the legal side. In the UK, using anabolic steroids without a prescription can have legal consequences.

Even with a potent blend like Mass 400, remember that it enhances your effort—it doesn’t replace it. Your results still depend on your training, nutrition, and recovery.

Buy Mass 400 Online

Looking to buy Mass 400 online in the UK or Europe? At Medicine4Me, you can order Mass 400 safely and discreetly. This high-strength anabolic blend is formulated to help you gain lean muscle mass, improve strength, and enhance endurance while supporting faster recovery between workouts. Each vial is produced by trusted pharmaceutical manufacturers like Opal Pharma, ensuring you receive genuine, high-quality products you can depend on.

Where to Buy Mass 400?

When you order Mass 400 from Medicine4Me, your package is delivered securely in plain, neutral packaging, with fast and tracked shipping straight to your door. Our team provides 24/7 customer support, so you’ll always have help if you have questions about your order or product use.