 The mine is actually a cast block of TNT with a thin coating of fibreglass.The mine has a central fuze well that normally uses a P-62 pressure fuze, although it can be used with any of the fuzes designed for the Russian TM-62 and TM-72 series of mines.The bakelite plastic used in the fuze of a MAT-76 may become brittle in desert conditions, which can reduce the activation pressure.