Yes , I'm aware of the fireman's tanks and that it's needed for a lot of guns , so is the 4500psi ;if you want a lot of fills. but I hope if this works out and I think it will , it will show not everyone " needs" the bigger tanks or the higher pressure tanks . It all depends on the gun you're going to be filling with it. This is one of those dark things that nobody ever brings up about PCP's ; that needs to be clarified .Especially for someone just getting started . I've seen the fireman tanks go for $200+ but then you have to have the valves and fitting to use the tank, which could run another $200+ and once you get all your equipment , you may not find a place that will or can fill it. My Air Arms Carbine gets 53 fills from a 3300psi 100cf tank that I have now. Today, I filled it to 190 bar which is about 2750psi , I shot approx 25 sight in shots, then shot a 50 shot match , for 75 shots and still had 130 bar(about 1800psi) showing on my guns gauge. I could shoot and have shot down to 110 bar before the poi drops. If I get 4-5 fills off this 13cf aluminum tank that's light weight and cost only $135 and works with all the equipment I already have , I think Ive found something that's hardly ever mentioned. kirby