The Pentel Prime Mechanical pencils offer Pentel quality in an economy Pencil. The built-in molded grip is grooved for greater comfort during extended writing periods. Each Mechanical Pencil is pre-loaded with Pentel super Hi-Polymer “HB” lead, which never needs sharpening, is super strong and produces a clear dark line. Prime pencils are available in a 0. 7mm lead size, which writes medium lines. The long-lasting, latex-free eraser is refillable (model pbde-1). the pencils are backed by pentel's limited lifetime .