Frequency wise, polymer capacitors exhibit a stable capacitance up to their roll-off frequency which can be up to a MHz which exceeds aluminum electrolytics. Due to their volumetric efficiency, polymers have much more capacitance per unit volume and one polymer can typically be used to replace a bank of MLCCs or as an alterative to large profile aluminum electrolytic can. Also compared to MLCCs, polymers do not exhibit piezo noise or have risk of flex cracks. Due to their lower ESR, polymers can handle much higher amounts of ripple current compared to wet aluminum electrolytics. Polymer also has benefits over the older tantalum technology, MnO₂. One of the biggest disadvantages of MnO₂ is that it has an ignition failure mode. The polymer cathode system eliminates the mechanism that causes the MnO2 to ignite. Polymers also have better derating guidelines compared to MnO₂, so less polymers are needed to handle the same voltage rails.