ON Serious Mass: The Ultimate Weight Gainer for Serious Size

1,260 calories & 50g protein per serving. Build mass, support recovery, and fuel your biggest gains.

Pack on serious size with Optimum Nutrition Serious Mass. This high-calorie weight gainer delivers 1,260 calories and 50g of protein per serving to fuel intense muscle growth and recovery. Designed for hard gainers and athletes, it provides the essential calories, protein, and nutrients needed to:

• Support rapid weight and muscle gain

• Enhance post-workout recovery

• Increase daily calorie intake easily

• Build the physique you want with consistent use

Rich Chocolate flavor, 12lbs per tub. Mixes easily for a quick, calorie-dense shake between meals or after training.

Fuel your mass goals. Start gaining seriously with ON Serious Mass.