A receptacle connection assembly includes a printed circuit board defining two spaced slots in a front edge portion with a mating tongue formed therebetween, a plurality of pads formed on two opposite surfaces of the mating tongue in a diagonally symmetrical manner for a flippable usage and a metallic shield including a tubular capsular portion assembled to the PCB to enclose the mating tongue. The tool holder hole is nominally smaller than the tool shank to be therein but upon heating of the insert expands to a size permitting insertion of the tool shank and, upon cooling, shrink fitting therein. A plurality of vent ports 7 connected to vacuum pumps 8, 9 are provided for reducing the pressure in the chamber. Thereafter, thermal processing is performed at a temperature of about 1000\xb0 C. Each roller wheel is carried at the distal end of a rocker arm attached by its near end to the lower end wall of the oven below a corresponding drum opening. The control arms can also provide a ducting means for ballast pumps on the master vessel.