Electronic Products Tools A B an Electronic Product is a system made of components which can be controlled a design specification is a series of statements which describe the possibilities & restrictions of a product monostables always use a combination of a capacitor and resistor to give the delay resistance is a property of materials which determines how easily charge can flow through them at a particular voltage capacitors store electrical energy by separating positive and negative electrical charges astables produce pulsed outputs they are often used to control flashing lights and audible outputs single pole single throw SPST single pole double throw SPDT double pole double throw DPDT resistors are made in a range of values known as the preferred values series