Abstract: An improved wrench has clamping or gripping jaws at each end of an elongated handle, and is configured as an open-end type, ring or polygonal socket wrench. The clamping jaws are disposed in two separate, non-parallel planes and are extended into the handle, intersecting therein at an angle varying from 90 to 170 degrees, such that handle has a biplanar structure of greatly enhanced strength.

Abstract: A circular cutting blade is provided in which the body is a synthetic fiber glass reinforced material which has a metallic hub and an outer cutting ring made from high speed steel, tungsten carbide, ceramic material or other cutting materials for a particular application. The outer cutting ring has an inwardly projecting tenon portion that has periodic trapezoidal recesses. The body of the blade is integrally molded about the tenon filling the recesses with the molded body to form torque projections to ensure that the outer ring is driven integrally with the blade body during cutting operations.

Abstract: A plastic wrench consitsint of a handle (2) and a gripping head (3,4), having a polygonal opening (5,6) in which there is embedded an open metal insert (10,11), likewise polygonal, and the walls of which form gripping jaws, wherein the walls (12,13,14,15) of the insert (10,11) forming the jaw are parallel and protrude slightly from the lateral faces (16-19) of the openings (5,6) of each gripping head (3,4), whereim the metal insert (10,11) is made from a hard, flexible and resilient metal having a coefficient of hardness of between 45 and 50 HRC, and wherein, in the region of the jaws (12-15), the thickness E2 of the insert (10,11) is between 0.5 and 0.7 times the thickness E1 of the gripping head (3,4).

Abstract: An elongated flat plastic box hinged along one side is provided with a pair of latches spaced along the opposite side. The male part of the latch is connected to an actuating tab formed in the top at one end and in the bottom at the opposite end of the elongated box. The female part of the latch is formed in the opposite part of the box in mating relationship with the male portion of the latch. This alternating arrangement allows the normal twisting action of left and right hands attempting to open the box, to disengage the latches and simultaneously open the box for exposure of the contents by simply applying pressure to the actuating tabs. The entire box, including the latches, is molded in a single operation.