When combined with the 2000 Series filters or 6000 series cartridges this respirator is on of the lightest reusable respirator available. It's cost- effective and can be washed and reused many times. The 6000 is lightweight with easy to adjust headstraps and a low-profile design for better visibility allows safety glasses to be worn . Very easy to use-no retainer or extra parts needed to attache the filters/cartridges to the facepiece. Three sizes available (small, medium and large).