Abstract: A hand held knife for use in cutting carpet pads. A speciality type utility knife used principally for cutting carpet pads has a handle configured such that a straight edged cutting blade releasably held in the handle provides a slicing action in contrast to a cutting action on the carpet pad. The knife unit is fabricated with two substantially mirror image halves which are divided at a median plane. A thumbwheel rotatably mounted in one of the halves and threadably engaged with the second half permits the ready separation of the two halves a distance necessary for rotation of one-half with respect to the other for the removal of a knife blade from an internal storage compartment and its insertion in the proper cutting position. Because of the simplicity of the separation of the components and the slicing action of the knife blade, fatigue to a user of this device is substantially reduced.