A hammer for use in a rotatable hammermill assembly comprising a first end for securement within a hammermill assembly, wherein a rod hole is formed in the second end, wherein the rod hole is centered in the first end for engagement with and attachment to the hammermill assembly is disclosed. When d1, d2, d3, and d4 respectively represent the concentrations of p-type impurities in the respective channel regions of the TFTs, at least three values out of d1, d2, d3, and d4 are mutually different, and d1, d2, d3, and d4 satisfy relations of d1<d2 and d3<d4. The user’s approximate current location may be determined by location-based technology.