Abstract: A comb includes a hollow frame having a pair of fixed teeth at opposite ends thereof, and a cap having a depending body portion disposed within the hollow interior of the frame. A series of transversely extending open slots in one longitudinally extending side planar face of the body portion receives individually a series of axially rotatable rod-like teeth. Each one of the open slots is four-sided in cross-sectional shape, and the fourth side is open in the plane of the face. The depth of the slots is greater than the thickness of the teeth so that the teeth fit entirely within the slots. In one embodiment of the present invention, the teeth are made by rotating axially rod stock and moving a cutter having the configuration of the desired shape of the teeth into cutting engagement with the rod stock.

Abstract: A calculator adapted to be used with a push button telephone having an array of telephone push buttons for serving both as a calculator and as an enlarger for the push buttons to facilitate the actuation of them, includes a first array of finger discs corresponding to at least some of the telephone push buttons and extending from a cup-shaped housing having an open mouth adapted to fit over the array of telephone push buttons, the first array of finger discs enabling the user to actuate the telephone push buttons. Logic circuits are mounted within the housing for performing mathematical calculations, and a display device mounted on the housing responds to the logic circuits for indicating information concerning the calculations. A first set of switches are mounted on the housing and respond to the finger discs for causing the generation of input information for the logic circuits.