Abstract: A self-defense knife has a handle and a blade. A user of the knife preferably holds it by the handle such that the blade extends toward the elbow of the user. The blade has a blunt edge and an opposite sharp edge. The knife is preferably held, more particularly, such that the blunt edge rests against the soft underbelly of the user's forearm. By holding the knife that way, the user is less likely to harm him or herself during use, and is also more likely to maintain the sharp or cutting edge in proper position for fending off an aggressor. The blunt edge is given a shape and arrangement that generally defines a reverse curve of the curve defined by the user's partly flexed wrist and forearm. The curve of the blunt edge thereby closes up a possible gap that could exist between the blunt edge and forearm. That way, an aggressor cannot grab the wrist of the user without also grabbing the sharp edge.

Abstract: A device having a surface which is adapted to be gripped by a user wherein the surface reduces slippage at the user's hand. The surface geometry of the handle portion substantially reduces slippage that can occur when an instrument is in use. Preferably, the hand held instrument is a knife. The surface of the handle is covered with protuberances having angled planar upper surfaces which create a plurality of edges designed to minimize hand slippage.