Honestly my friend you cannot add the Mast to the NPP/Prop esters. This will cause a crash, and you will not be able to salvage it (trust me on this). The two esters of NPP/Prop can be mixed together at 100/100. With the addition of mast. you will get a crash as two esters of the same chemical function will not be able to supersaturate and remain stable. I highly suggest not making it with mast. you can do Mast/Prop mix at a low Mg/Ml though.