Many sound designers offer "teaser" packs. For example, a company might sell "X Noise Waves Vol. 1" for $50 but offer "X Noise Waves Vol. 1 - Demo Pack" for free, containing 25 samples. These are fully legal. You can use them in commercial projects without fear of lawsuits.
When searching for "X Noise Waves free download," you will encounter two types of results: and Pirated Content.
Unlike standard gates, X-Noise uses a "noiseprint" system to target specific frequencies: