The Combi actually comes with a pre-filter that goes on the end of its hose, but I just put a coffee filter over it with a rubber band for extra protection and ease of cleanup. Not only is the Katadyn Combi a silver ceramic/carbon filter, it is also the hardiest and most durable on this list, bar none. Those pen filters and bag filters may be rated for 100,000 gallons, but they’ll never last long enough to make it past 1/10th of that number in real world use. The Combi was even standard issue to the Swiss military mountain units. There’s a reason why Combis are $200 and Sawyers are $20. The drawbacks of the Combi are weight, size, moving parts, price, the fact that it needs a hose, and that it was recently discontinued by Katadyn in favor of the less-effective, $400 Katadyn Pocket (sheesh). The silver ceramic replacement filters are expensive. Each Combi filter costs about $100 and lasts for 13,000 gallons; so you won’t need but a few, and deals may be had as retailers sell off their remaining inventory. Every new Combi comes with both a ceramic and carbon filter installed. The Combi offers carbon filtration, and in a SHTF scenario filtering chemicals out of the water may be even more important that killing pathogens. Even with the drawbacks this filter shines amongst the others.