Crain 189 Hook Handle Utility Knife has many added contours to provide improved grip and greater pulling power. It works especially well with hook blades on tough vinyl. The wide contoured midsection transitions to a narrow rear hook in proportion to the palm and fingers. The rear hook allows the little finger improved advantage for greater pulling power. The body is designed to pivot open by loosening the folding thumbscrew for fast access to replacement blades. The precision blade holder holds the blades tightly even at extended length.