There is only one company that legally sells true 4K Blu-ray quality downloads: .

In the landscape of digital home theater and unauthorized content distribution, the term "Remux" represents the highest tier of video quality available outside of physical media. Unlike "transcodes" or "WEB-DLs," a Remux aims to preserve the original commercial optical disc's data stream without quality loss. The addition of "Exclusive" typically denotes a release by a specific piracy group that claims first access or unique sourcing, or it refers to the fact that the 4K master is exclusive to the physical medium and not available on streaming services.