Freemax M Pro 2 Tank is equipped with military-grade SS904L mesh and Tea Fiber Cotton formula (95% Tea Fiber Cotton plus 5% Organic Cotton), which is originally compatible with Freemax 904L M1, M2, M3, and M4 Mesh Coil. But the only difference between the metal edition and the resin edition of M Pro 2 is the metal comes with Child Resistant Top Fill Design and CRC qualified, while the resin one has three steel balls into the top cap to increase friction.
However, Freemax M Pro applies the Freemax patented cotton formula, which is 90% Flax Cotton Fiber and 10% Cotton Fiber, and this is the reason why the Freemax Multiple Mesh Coils have an average lifespan of about 2-3 weeks. There are single/double/triple/quad/ quintuple mesh coils compatible with M Pro Tank.
Note: Both utilize the top fill design, plus, the M Pro mesh coil and SS904L M Mesh Coils can be compatible with any tank of M Pro Series.
For more information about Freemax M Pro Series Tanks, please enter here>> https://www.freemaxvape.com/tanks