Pocket Knife by Boker Plus. BOKER PLUS VINTAGE SERIES. With this new series Boker Plus offers the same high quality materials well known precision in manufacturing and the sharp look and fine details of the more modern Boker Plus knives. These traditional double bolster knives take us back to the good ol times. Fine polished brass bolsters and synthetic handle scales with inlay for engraving. The blades are made of high performance 440C stainless steel. Available in seven models. Same specifications as model 01BO294Y but with a black synthetic handle. Blade length: 3-1/8 . Overall length: 7 . Weight: 2.8 oz.