We are authorised resellers of Oxy Powder and the product we send out is the genuine product - both versions are exactly the same product. The UK version of Oxy Powder is labelled as 'Time Released Oxygen Magnesium Compound' whereas the US version is labelled as 'Oxygen Based Intestinal Cleanser'.
The reason for the difference is that EU labelling laws requires that the UK label is different to the US, hence the different label and description, as well as dose. In the US, GHC are able to list the magnesium salt compound as the ingredient but for the UK/EU they are required to break down the minerals oxide and hydroxide.
Another difference in the label is that the US version of Oxy Powder states the ingredients per dose of 4 capsules whereas the EU/UK version states it per capsule. The US serving size is 2746mg (for 4 capsules), whereas the EU/UK version is labelled as 687mg per capsule. You would need to multiply the UK version by 4 to have a like for like comparison = 2748mg.