Additional mask files

I used the tool “Extract by Mask” to clip a raster. It resulted in 5 tif images: mask, maskc1, maskc2, maskc3, and maskc4. What are the maskc1-4 files? They’re large and I’d like to delete them if they won’t effect my normal mask tif. I’m trying to preview them in ArcCatalog but it’s taking forever to build pyramids.