Abstract: A screw-operated dispenser providing for prevention of breakage of an engaged screw when a user rotates a turn member in the wrong direction, i.e., repels rather than propels an elevator. A tubular body holds a supply of product, which is dispensed by action of the elevator along a threaded shaft upon turning a base to either propel or repel the elevator along the shaft which is threadably engaged with the elevator. Certain lowermost revolutions of the thread on the shaft are chamfered at the bottom edge thereof so that when the elevator is in a lowermost position on the screw shaft and a user mistakenly rotates the turn member in a repel direction, the thread of the elevator will not engage, i.e., will override, the thread of the screw shaft thereby eliminating stress and/or pressure between the threads which may result in breakage of the screw shaft and render the dispenser inoperable.

Abstract: A screw-operated dispenser providing for prevention of breakage of an engaged screw when a user rotates a turn member in the wrong direction, i.e., repels rather than propels an elevator. A tubular body holds a supply of product, which is dispensed by action of the elevator along a threaded shaft upon turning a base to either propel or repel the elevator along the shaft which is threadably engaged with the elevator. Certain lowermost revolutions of the thread on the shaft are chamfered at the bottom edge thereof so that when the elevator is in a lowermost position on the screw shaft and a user mistakenly rotates the turn member in a repel direction, the thread of the elevator will not engage, i.e., will override, the thread of the screw shaft thereby eliminating stress and/or pressure between the threads which may result in breakage of the screw shaft and render the dispenser inoperable.

Abstract: A level of the type having parallel working surfaces and an interconnecting web is provided with an aperture having at least a pair of oppositely directed notches prearranged and configured relative to each other so that ends of a level vial accurately fit within the notches. The vial is provided at one end with a vial retaining tongue that extends from one end thereof and abuts one side of the web to laterally position and orient the vial within the plane of the web. The assembly includes a vial retainer cover that overlies the aperture and includes a vial engaging abutment that bears against the tongue of the vial to hold that member in retentive butting engagement against the side of the web and prevent lateral displacement or misorientation of the vial. The elongated vial may have a gradually tapered surface that not only permits rapid molding of the vial but also facilitates the use of a curved vial configuration with the proper degree of curvature accurately molded therein.