Transcriptional activator that plays a regulatory role in the development of secondary cell wall fibers. Is a direct target of SND1. Expressed in protoxylem and elongating interfascicular fiber cells of elongating internodes, developing metaxylem cells and interfascicular fibers of non-elongating internodes and developing secondary xylem of roots. The NAC domain includes a DNA binding domain and a dimerization domain. Truncated N-terminus.