Brand: Optimum Nutrition

Optimum Nutrition Serious Mass 12Lbs

$169.90

Flavour: Chocolate

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Optimum Nutrition Serious Mass 12lb

If you’re serious about gaining size, this is the tool. Optimum Nutrition Serious Mass 12lb is a high-calorie mass gainer designed to help you increase body weight, build muscle, and stay in a consistent calorie surplus.

Each full serving delivers over 1,250 calories, 50g of protein, and 250g+ of carbohydrates, giving your body the fuel it needs to grow. Whether you have a fast metabolism or struggle to eat enough food daily, this makes hitting your calorie target simple.

The 12lb size is built for consistency — fewer reorders, better value per serve, and a reliable way to stay on track with your goals.

🔥 Featured Highlights

1250+ calories per serving for weight gain
50g protein blend (whey, casein & egg)
250g+ carbohydrates for energy & recovery
Supports muscle growth & size increases
Includes creatine, glutamine & amino acids
Added vitamins & minerals
Large 12lb size = best long-term value

💪 Why Use Serious Mass?

If you're not gaining weight, you're not eating enough — it’s that simple.

Serious Mass gives you a huge calorie boost in one shake, making it easy to stay in a surplus without forcing massive meals.

This makes it ideal for:

Hard gainers / fast metabolisms
Bulking phases
People who struggle with appetite
Post-workout recovery + calorie loading

📦 Directions for Use

Mix 2 heaping scoops with 500–700ml of water or milk.

Tip: Start with half a serving and increase gradually — full servings are very high in calories.

🐶 Why TopDog Nutrition Recommends It

This is one of the most effective ways to gain weight — no guesswork.

If you’re struggling to grow, this solves the biggest problem instantly: not enough calories.

👉 Easy calories → consistent surplus → real size gains

Simple, proven, and built for results.

⚠️ Disclaimer

This product is not intended to diagnose, treat, cure, or prevent any disease. Results may vary depending on diet, training, and individual response.

FREE SHIPPING ON ALL ORDERS $60 AND OVER
TopDog charges a flat rate of $3.90 for shipping on all orders under $60. If your order equals more than $60 shipping is FREE. Additional charges on all orders apply for Rural or Signature Deliveries.

RURAL $6.90 surcharge applies Alternatively you could send to a town or workplace that is not a rural delivery address.

SIGNATURE REQUIRED $2.00 surcharge applies

At TopDog we're committed to giving you the best possible deals on high-quality supplements.

As a proud, small, New Zealand-based company, we work hard to source products at the lowest cost. This focus on maximum savings over massive inventory means our shipping times are a little different:

Standard Delivery Time: 2-7 Working Days
Why the range? This timeframe allows us to source your items efficiently while securing the low prices you love.

We promise we're doing our absolute best to get your order to you as quickly as possible— we never intentionally delay orders. Your patience helps us keep our prices competitive!

If you discover any defect in your product, you may within 5 days of delivery return the item in new condition for a replacement. If a replacement is not available we may at our discretion provide a refund. All clearance products are non-refundable and are marked as such on the product listing & collection page. You will be notified by email of the status of the replacement. For any claim to be made the item must be sent to our current shipping address as provided by emailing info@topdognutrition.co.nz.

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