These are genuine OEM Windsor replacement paper bags for the Windsor® and Versamatic upright vacuums. They come 10 per pack, and should be checked each time before using your vacuum. A nearly full bag restricts air flow causing your vacuum to perform at less than optimal levels.

Windsor is a Karcher company, and they say they their warranty guarantee is invalidated if replacement parts (i.e. bags, filters, brush roller, etc.) are not OEM or Original Equipment Manufacturer parts.