The Bulk Protein Company | Serious Gainz Mass Gainer - 5Kg Banana Gain Supplement The Bulk Protein Company | Serious Gainz From The Bulk Protein Company Is One Of Our Most Popular Protein Powders And Mass Gainers. After Taking The Uk By Storm, It\'s Now Become A Best-Seller With Tons Of Great Reviews You Can Read Above. Serious Gainz Fact Sheet: 30 Grams Of Protein Per Serving 468 Calories Per Serving Huge 5Kg Tub ! Amazing Flavours & Taste ! Try Your First Tub Of Serious Gainz 5Kg Today And Discover This Incredible Product. | Serious Gainz Mass Gainer - 5Kg Banana