If you got the standard 3ml, 5ml, or the 5.5 phat a regular or lr boge carto should fit, the 3 ml dual, 5ml dual and 8.5 BFT use a dual coil mega carto. Oops almost forgot that the 3ml also comes in a 901 configuration as well.... The carto on the regular
tanks does not come up to the top with the bottom of the carto flush with bottom cap. The inner O ring will seal around the top of the carto preventing leaks. On mine there is a more than 1/8 inch difference from the top of the carto to the top of the end cap. The drip tip that came with mine hides the flat portion at the bottom of the tip (above the O ring on the tip), and the sweeping side comes even with the top of the tank end cap when installed. hope this helps....