Are there small or large pieces of magnesium in FRH?

In a Flameless Ration Heater (FRH), the magnesium is typically in the form of small shavings or powder. These small magnesium pieces are designed to react with water to produce heat through an exothermic chemical reaction. The surface area of the magnesium is increased in smaller pieces, allowing for a faster reaction and more efficient heat generation within the FRH.