NGK B7HS Spark Plug NGK B7HS spark plug for various makes and models including most older 125-150 Vespas from the 1950s-1990s, all small frame Vespas, P125X, PX150 and much more.NGK traditional plugs are constructed for longer life and optimum performance. Corrugated ribs prevent flashover. NGK uses only the purest alumina silicate in its ceramic insulator which give all NGK plugs greater strength and better heat transfer. Copper cored and triple sealed to further aid in heat removal and prevent interior leakage. T hread Size: 14mm Reach: 12.7mm (1/2 inch) Hex Size: 20.6mm (13/16 inch) Gap: 0.7mm (.028 inch) Heat Range: 7Removable Terminal Nut