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Cookies and cream

Best flavour ordered chocolates one this time 💪🏻

Fantastic stuff

Love this stuff has helped me put on the weight that was needed. Use it as part of breakfast and as a post workout

Not just for gaining weight

I use this for breakfast and pre training for fuel and with the high amount of carbs it’s an easy option pre training or pre race. Strawberry and chocolate flavours are great

Need help? Email or DM us on @nisupplements

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Optimum Nutrition Serious Mass

Name: Optimum Nutrition Serious Mass 5.4kg
Brand: Optimum Nutrition
SKU: P4253S
Price: 49.99 GBP
Availability: InStock

Serious Mass is the ultimate in weight gain formulas. Serious Mass supplies you with the tools you need to pack on the pounds and develop the physique you've always wanted.

1250 Calories per serving in water

1640 Calories when made with low-fat milk

Over 250 g of carbohydrates - with no added sugar

Includes Creatine, L-glutamine & Glutamine Peptides, Choline, Inositol, and MCTs

Source of protein: contains 50 g of protein per serving

Nutritional Information Per Serving (based on Cookies & Cream Flavour)

Energy: 1266 kcal / 5297 kJ

Protein: 50 g

Total Carbohydrates: 252 of which Sugars: 26 g

of which Dietary Fiber: 0.6 g

Fat: 6.2 of which Saturates: 3.2 g

Salt: 3.4 g

Amounts Per Serving (based on Cookies & Cream Flavour

Vitamin A: 306 µg, Vitamin D: 1.9 µg, Vitamin E: 3.6 mg, Vitamin C: 22 mg, Thiamin: 0.53 mg, Riboflavin: 0.67 mg, Niacin: 6.9 mg, Vitamin B6: 0.76 mg, Folic Acid: 75.2 µg, Vitamin B12: 12 µg, Biotin: 56 µg, Pantothenic Acid: 2.2 mg, Potassium: 302 mg, Chloride: 1099 mg, Calcium: 417 mg, Phosphorus: 189 mg, Magnesium: 17.4 mg, Iron: 1.4 mg, Zinc: 0.81 mg, Copper: 0.10 mg, Manganese: 0.17 mg, Chromium: 39 µg, Iodine: 15.3 µg, Sodium: 416 mg

Cookies & Cream:Maltodextrin, Whey Protein Concentrate, Calcium Caseinate (Emulsifier; Soy Lecithin), Flavourings, Cookie Crumb (1.4%) (Wheat Flour [Gluten], Sugar, Fully Hydrogenated Vegetable Fats; Palm and Rapeseed in varying proportions; Fat-Reduced Cocoa Powder), EGG Albumen, Sodium Chloride, Medium Chain Triglycerides, Dipotassium Phosphate, Creatine Monohydrate, Choline Bitartrate, L-Glutamine, Glutamine Peptides [Gluten], Whey Powder, Inositol, Vitamin Blend (L-Ascorbic Acid, Nicotinamide, DL-Alpha-Tocopheryl Acetate, Calcium D-Pantothenate, Pyridoxine Hydrochloride, Riboflavin, Thiamin Hydrochloride, Retinyl Acetate, Pteroylmonoglutamic Acid, D-Biotin, Cholecalciferol, Cyanocobalamin), Sweetener (Sucralose), Magnesium Oxide, Potassium Chloride, Ferric Pyrophosphate, Zinc Oxide, Cupric Gluconate, Manganese Sulphate, Chromium (III) Chloride Hexahydrate, Potassium Iodide

Delivery Terms & Conditions / Options & Info

Operated by Nutrition & Internet Supplements Limited (trading as NI Supplements). Last updated: 13 October 2025

Cut-off & processing: Orders placed before 1 p.m. (UK time) are processed the same working day. Courier networks operate Monday–Saturday (excluding Bank Holidays). Delivery times below exclude Sundays unless stated.

UK Mainland (excluding Highlands & Islands)

Orders under £50

Service	Price	Speed	Notes
1–2 Day Delivery (No Signature Required)	£2.95	Fully tracked; 91% delivered next day if ordered before 1 p.m. (excl. Sundays)	Photographic & GPS delivery proof confirms delivery. Non-delivery claims are investigated; parcels confirmed delivered by Royal Mail are not eligible for replacement.
1–2 Day Delivery (Signature Required)	£3.35	Fully tracked; 91% delivered next day if ordered before 1 p.m. (excl. Sundays)	Signature required at delivery.

FREE delivery on orders over £50

Service	Price	Speed	Notes
4–5 Day Delivery (No Signature Required)	Free	Fully tracked (excl. Sundays)	Terms for “No Signature Required” (photo/GPS proof) apply.
4–5 Day Delivery (Signature Required)	Free	Fully tracked (excl. Sundays)	Signature required.

Reminder: Selecting “No Signature Required” means your parcel may be left at your address or a designated safe location without a signature, with photo/GPS proof used to confirm delivery.

Northern Ireland

Service	Price	Speed	Notes
Free Delivery on Orders Over £50	Free	2–3 working days	Fully tracked.
Express (No Signature Required)	£1.99	Next-day if ordered before 1 p.m. (excl. Sundays)	Photo/GPS proof confirms delivery.
Express (Signature Required)	£2.49	Next-day if ordered before 1 p.m. (excl. Sundays)	Signature on delivery required.

Note: We guarantee same-day dispatch for express items ordered before 1 p.m.; courier delays can occasionally occur.

Ireland

Service	Price	Speed	Notes
Free Delivery on Orders Over £70	Free	2–4 working days	Fully tracked; order before 1 p.m. (excl. weekends)
Reduced Rate on Orders Over £50	£2.99	1–2 working days	Parcelforce/GLS; fully tracked (excl. weekends)
Express on Orders Under £50	£4.99	Next-day if ordered before 1 p.m.	Fully tracked; Mon–Fri dispatch; courier delays may occur
Standard on Orders Under £50	£4.99	1–2 working days	Parcelforce/GLS; fully tracked

EU & International Shipping

All international shipping rates are shown at checkout.

Customs notice: If your parcel is held or delayed by customs, neither NI Supplements nor the courier can obtain more detail than the status shown on your tracking. Customs operate independently and, following Brexit, occasional delays are unavoidable. These delays are outside our stated delivery times and are not our responsibility. We cannot contact customs to expedite orders.

Agreement: By completing your order and ticking the checkout box, you agree to these delivery terms for EU/international shipments.

UK Mainland (excluding Highlands & Islands)

Orders under £50

Service	Price	Speed	Notes
1–2 Day (No Signature)	£2.95	Tracked; 91% next-day before 1 p.m.	Photo/GPS proof confirms delivery; confirmed deliveries not eligible for replacement.
1–2 Day (Signature)	£3.35	Tracked; 91% next-day before 1 p.m.	Signature required.

FREE on £50+

Service	Price	Speed	Notes
4–5 Day (No Signature)	Free	Tracked	Photo/GPS proof terms apply.
4–5 Day (Signature)	Free	Tracked	Signature required.

Northern Ireland

Service	Price	Speed	Notes
Free on £50+	Free	2–3 working days	Tracked
Express (No Signature)	£1.99	Next-day before 1 p.m.	Photo/GPS proof
Express (Signature)	£2.49	Next-day before 1 p.m.	Signature required

Ireland

Service	Price	Speed	Notes
Free on £70+	Free	2–4 working days	Tracked; order before 1 p.m.
Reduced Rate on £50+	£2.99	1–2 working days	Parcelforce/GLS; tracked
Express under £50	£4.99	Next-day before 1 p.m.	Tracked; Mon–Fri dispatch
Standard under £50	£4.99	1–2 working days	Parcelforce/GLS; tracked

EU & International

Rates shown at checkout.

Customs: Customs delays are outside our delivery times and not our responsibility; we cannot contact customs to expedite.

General Delivery Terms

No Signature Required: By selecting this option you agree your parcel may be left at the delivery address or a designated safe location without a signature. Photographic and GPS proof from the courier confirms delivery. Claims of non-delivery will be investigated, but parcels confirmed delivered are not eligible for replacement.
Signature Required: A signature will be obtained at delivery; choose this for added security.
Same-day dispatch (express): Guaranteed for orders placed before 1 p.m. Courier delays can occasionally occur.
Working days: Processing Mon–Sat (excl. Bank Holidays). Deliveries do not include Sundays unless stated by the service.
Cut-off: Orders after 1 p.m. are processed the next working day.

Failed Delivery & Returns to Sender

If an order is returned due to customer error (e.g., failure to take delivery or arrange collection/redelivery), a re-shipping fee applies. Alternatively, a refund of the item price minus our shipping costs can be provided. If the error is ours, we will re-ship at our expense.

Questions about shipping?

For queries on shipping times and order status please email hello@nisupplements.com.

Nutrition & Internet Supplements Limited (trading as NI Supplements)
Unit 5, Graham Industrial Park, Dargan Crescent, Belfast, Co Antrim, BT3 9LP, United Kingdom