From the link here: https://www.purinamills.com/horse-feed/products/detail/purina-replenimash-product
Wheat Middlings; Dried Plain Beet Pulp; Barley; Dried Carrot; Seaweed-Derived Calcium; Salt; Soybean Oil; Flaxseed; Magnesium Oxide; L-lysine Monohydrochloride; Dicalcium Phosphate; Cane Molasses; Beet Molasses; Vitamin E Supplement; Vitamin D3 Supplement; Zinc Oxide; Copper Sulfate; Vitamin A Supplement; Calcium Iodate; Calcium Carbonate; Cobalt Carbonate; Ferrous Carbonate; Manganous Oxide; Sodium Selenite
It’s basically beet pulp + Outlast (or at least the buffer ingredient from it) + electrolytes. The NSC is pretty high at 25ish percent but with a relatively low feed rate (1-2lbs), it shouldn’t pose an issue unless the horse has metabolic concerns.
My picky TB will start nickering when he sees the bucket coming and scarfs it like candy. Nice to keep on hand as a little hydration boost after hard work or hot weather.