The 531 Pardue is ultra-lightweight and very thin, you'll hardly even know it's in your pocket. The black and gray herringbone G-10 handle scales help keep the knife's weight down but keeps it very durable. The AXIS lock, dual thumb studs and reversible pocket clip make the knife usable for right and left handers. The Pardue 531S has a stonewashed blade with a partially serrated edge.