Distribute high tension current to spark

Insulate spark plug electrodes

Prevents arcs at the points

Open and close the primary circuit

Improve combustion swirl

Increase the fuel pressure

Improve fuel atomisation

Helps for the complete ignition

Helps in easy fitting

Produce correct alignment

Provide clearance space

Produce good sealing

Spark plug will run cooler

Life of spark plug increased

Spark plug will run hot

Improper atomisation

Acts as contact breaker

Prevents dirt, carbon into distributor

Conduct the ignition surge to the electrode

Distribute high tension surge to ignition coil