Cascade Filt-A-Pack Pro-Carb-Z Activated Carbon & Zeolite Filter Bags for Cascade Cannister Filters, 4-pack Convenient, ready-to-use filter bags for use with your Cascade cannister filter. Each Bag contains Pro-Carb laboratory quality activated carbon with Pro-Z ammonia removing zeolite crystals. Fits easily into all Cascade cannister filters. Filter media fully enclosed in a disposable nylon-mesh bag. Also fits many other branded cannister filters.