TN 613020 Professional Series Replacement Vac Bags. 99% Micro Filtration. Provides up to 40% Increased Airflow. Janitized Vacuum Bags for Nobles TrailBlazer XL Back Pack Vacuums, 10/pk. Replaces Castex/Nobles/Tennant Part #613020. These are packed 10 per pack. If multiple packs are ordered, we will bulk ship and reduce your freight charges during processing. Check your model before ordering since we also offer a TrailBlazer and TrailBlazer Lite series bag.